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. 2024 Jan 8;1(1):CD010216.
doi: 10.1002/14651858.CD010216.pub8.

Electronic cigarettes for smoking cessation

Nicola Lindson  1 , Ailsa R Butler  1 , Hayden McRobbie  2 , Chris Bullen  3 , Peter Hajek  4 , Rachna Begh  1 , Annika Theodoulou  1 , Caitlin Notley  5 , Nancy A Rigotti  6 , Tari Turner  7 , Jonathan Livingstone-Banks  1 , Tom Morris  8 , Jamie Hartmann-Boyce  9
Affiliations

Electronic cigarettes for smoking cessation

Nicola Lindson et al. Cochrane Database Syst Rev. .

Update in

  • Electronic cigarettes for smoking cessation.
    Lindson N, Butler AR, McRobbie H, Bullen C, Hajek P, Wu AD, Begh R, Theodoulou A, Notley C, Rigotti NA, Turner T, Livingstone-Banks J, Morris T, Hartmann-Boyce J. Lindson N, et al. Cochrane Database Syst Rev. 2025 Jan 29;1(1):CD010216. doi: 10.1002/14651858.CD010216.pub9. Cochrane Database Syst Rev. 2025. PMID: 39878158 Free PMC article.

Abstract

Background: Electronic cigarettes (ECs) are handheld electronic vaping devices which produce an aerosol by heating an e-liquid. People who smoke, healthcare providers and regulators want to know if ECs can help people quit smoking, and if they are safe to use for this purpose. This is a review update conducted as part of a living systematic review.

Objectives: To examine the safety, tolerability and effectiveness of using electronic cigarettes (ECs) to help people who smoke tobacco achieve long-term smoking abstinence, in comparison to non-nicotine EC, other smoking cessation treatments and no treatment.

Search methods: We searched the Cochrane Tobacco Addiction Group's Specialized Register to 1 February 2023, and Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and PsycINFO to 1 July 2023, and reference-checked and contacted study authors.

Selection criteria: We included trials in which people who smoke were randomized to an EC or control condition. We also included uncontrolled intervention studies in which all participants received an EC intervention as these studies have the potential to provide further information on harms and longer-term use. Studies had to report an eligible outcome.

Data collection and analysis: We followed standard Cochrane methods for screening and data extraction. Critical outcomes were abstinence from smoking after at least six months, adverse events (AEs), and serious adverse events (SAEs). We used a fixed-effect Mantel-Haenszel model to calculate risk ratios (RRs) with a 95% confidence interval (CI) for dichotomous outcomes. For continuous outcomes, we calculated mean differences. Where appropriate, we pooled data in pairwise and network meta-analyses (NMA).

Main results: We included 88 completed studies (10 new to this update), representing 27,235 participants, of which 47 were randomized controlled trials (RCTs). Of the included studies, we rated ten (all but one contributing to our main comparisons) at low risk of bias overall, 58 at high risk overall (including all non-randomized studies), and the remainder at unclear risk. There is high certainty that nicotine EC increases quit rates compared to nicotine replacement therapy (NRT) (RR 1.59, 95% CI 1.29 to 1.93; I2 = 0%; 7 studies, 2544 participants). In absolute terms, this might translate to an additional four quitters per 100 (95% CI 2 to 6 more). There is moderate-certainty evidence (limited by imprecision) that the rate of occurrence of AEs is similar between groups (RR 1.03, 95% CI 0.91 to 1.17; I2 = 0%; 5 studies, 2052 participants). SAEs were rare, and there is insufficient evidence to determine whether rates differ between groups due to very serious imprecision (RR 1.20, 95% CI 0.90 to 1.60; I2 = 32%; 6 studies, 2761 participants; low-certainty evidence). There is moderate-certainty evidence, limited by imprecision, that nicotine EC increases quit rates compared to non-nicotine EC (RR 1.46, 95% CI 1.09 to 1.96; I2 = 4%; 6 studies, 1613 participants). In absolute terms, this might lead to an additional three quitters per 100 (95% CI 1 to 7 more). There is moderate-certainty evidence of no difference in the rate of AEs between these groups (RR 1.01, 95% CI 0.91 to 1.11; I2 = 0%; 5 studies, 1840 participants). There is insufficient evidence to determine whether rates of SAEs differ between groups, due to very serious imprecision (RR 1.00, 95% CI 0.56 to 1.79; I2 = 0%; 9 studies, 1412 participants; low-certainty evidence). Due to issues with risk of bias, there is low-certainty evidence that, compared to behavioural support only/no support, quit rates may be higher for participants randomized to nicotine EC (RR 1.88, 95% CI 1.56 to 2.25; I2 = 0%; 9 studies, 5024 participants). In absolute terms, this represents an additional four quitters per 100 (95% CI 2 to 5 more). There was some evidence that (non-serious) AEs may be more common in people randomized to nicotine EC (RR 1.22, 95% CI 1.12 to 1.32; I2 = 41%, low-certainty evidence; 4 studies, 765 participants) and, again, insufficient evidence to determine whether rates of SAEs differed between groups (RR 0.89, 95% CI 0.59 to 1.34; I2 = 23%; 10 studies, 3263 participants; very low-certainty evidence). Results from the NMA were consistent with those from pairwise meta-analyses for all critical outcomes, and there was no indication of inconsistency within the networks. Data from non-randomized studies were consistent with RCT data. The most commonly reported AEs were throat/mouth irritation, headache, cough, and nausea, which tended to dissipate with continued EC use. Very few studies reported data on other outcomes or comparisons, hence, evidence for these is limited, with CIs often encompassing both clinically significant harm and benefit.

Authors' conclusions: There is high-certainty evidence that ECs with nicotine increase quit rates compared to NRT and moderate-certainty evidence that they increase quit rates compared to ECs without nicotine. Evidence comparing nicotine EC with usual care/no treatment also suggests benefit, but is less certain due to risk of bias inherent in the study design. Confidence intervals were for the most part wide for data on AEs, SAEs and other safety markers, with no difference in AEs between nicotine and non-nicotine ECs nor between nicotine ECs and NRT. Overall incidence of SAEs was low across all study arms. We did not detect evidence of serious harm from nicotine EC, but the longest follow-up was two years and the number of studies was small. The main limitation of the evidence base remains imprecision due to the small number of RCTs, often with low event rates. Further RCTs are underway. To ensure the review continues to provide up-to-date information to decision-makers, this review is a living systematic review. We run searches monthly, with the review updated when relevant new evidence becomes available. Please refer to the Cochrane Database of Systematic Reviews for the review's current status.

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Conflict of interest statement

RB holds a National Institiute for Health Research (NIHR) grant, but this did not directly fund this current work. RB is also supported by Cancer Research UK. She is principal investigator of an ongoing study listed in this review.

CB was principal investigator on the ASCEND e‐cigarette trial reported in the Cochrane Review and a co‐investigator on the ASCEND II trial and several other studies included in the review. CB reports research grants from the Health Research Council of NZ, the Heart Foundation of NZ and the NZ Ministry of Health (Monitoring the Illicit Tobacco Trade in NZ), the NZ Ministry of Foreign Affairs and Trade (estimating the numbers of tobacco and vaping retailers in NZ) and Auckland Council (Evaluation of the Smokefree Auckland Project). CB reports research grants from: Wellcome Trust UK, REFLECT Cool roofing trial; Health Research Council of NZ, Cess@tion trial, FASD studies; The University of Auckland Transdisciplinary Ideation Fund for The Collective website; Putahi Manawa Centre for Research Excellence in Heart Health Integrated Research Module grant; US NIH (via Wake Forest University): CENIC study; Education NZ Smoking cessation in China; Marsden Fund (NZ): Respiratory effects of vaping. He has recently led a project funded by Pfizer (NZ) on chronic disease management. CB is President of the Society for Research on Nicotine & Tobacco; Member of the Expert Working Group on Tobacco, Health Coalition Aotearoa; Member of the Scientific Advisory Committee of the Cancer Society of NZ; Member of the Scientific Advisory Committee of the RESPIRE research programme, University of Edinburgh; Member of the CREATE Tobacco Endgame Centre of Research Excellence, Australia. CB has carried out independent contractor consultancy for Johnson and Johnson in 2020 on NRT and to Kervue Inc. regarding setting up an ASEAN regional smoking cessation networking board.

ARB's work on this review has been supported by Cancer Research UK Project Award funding. This is not deemed a conflict of interest.

PH was principal investigator on three of the trials included in this review two funded by NIHR and one by CRUK and co‐investigator on other relevant studies.

JHB has received support for this work from the Cochrane Review Support Programme and the University of Oxford's Returning Carer's Fund. JHB been an applicant and pricipal investigator on project grants to carry out research in the area of tobacco control from National Institute for Health Research and Cancer Research UK. None of these are deemed conflicts of interest.

NL has received payment for lectures on systematic review methodology (Oxford University Hospitals NHS Foundation Trust), and has been an applicant and pricipal investigator on project funding to carry out research in the area of tobacco control from the NIHR Evidence Synthesis programme, Cancer Research UK (charity), Clarion Futures (charity), Oxfordshire County Council and the NIHR Oxfordshire and Thames Valley ARC, and Greater Manchester NHS Integrated Care. None of this is deemed a conflict of interest.

JLB was employed by the University of Oxford to work as a Managing Editor and Information Specialist for the Cochrane Tobacco Addiction Review Group before becoming an author on this review. During this time, he was involved in the editorial processing of the review. He is now an Editor for Cochrane. Since becoming an author, he has not been involved in the editorial process for this review. Core infrastructure funding for the Cochrane Tobacco Addiction Group was provided by the NIHR to the University of Oxford.

HM is an employee of Te Whatu Ora‐Health New Zealand. HM holds fellowships with New Zealand College of Public Health Medicine (NZCPHM represents public health medicine specialists); and the Society of Lifestyle Medicine. HM is a Professor in Public Health Interventions, University of New South Wales, National Drug and Alcohol Research Centre and provide mentorship and advice for the Tobacco Research Group. He is currently a named investigator on three smoking cessation trials that are all funded by the Australian National Health and Medical Research Council (NHMRC). HM is a named investigator of a smoking cessation trial at Queen Mary University of London, funded by the National Institute of Health Research. HM is a named investigator of a study that examines an approach to prevent e‐cigarette use among adolescents at University of Sydney, funded by the Australian National Health and Medical Research Council (NHMRC). HM is a co‐investigator on a number of studies included in this review. HM is a board Member, Rotorua Community Youth Centre Trust.

CN has received an honorarium from Vox Media for filming a 'nicotine explainer' on the role of nicotine in addiction. This is not deemed a conflict of interest. CN is a member of the advisory council for 'Action on Smoking and Health (ASH)'. CN is co‐PI on an ongoing trial (protocol) Cessation of Smoking Trial in the Emergency Department (CoSTED) ‐ National Institute for Health Research ‐ Health Technology Assessment. NIHR129438.

TM is funded by the National Institute for Health Research (NIHR) Complex Reviews Support Unit (CRSU) and supported by the NIHR Applied Research Collaboration East Midlands (ARC EM) and Leicester Biomedical Research Centre (BRC). The views expressed are those of the author(s) and not necessarily those of the NIHR or the Department of Health and Social Care.

NAR has received royalties from UpToDate, Inc. for chapters on electronic cigarettes and occasional fees from academic hospitals or professional medical societies for lectures on smoking cessation that include discussion of electronic cigarettes. NAR was a member of the committee that produced the 2018 National Academies of Science, Engineering, and Medicine's Consensus Study Report on the Public Health Benefits of E‐cigarettes. She was unpaid for this work. NAR is employed by Massachusetts General Hospital (MGH). Outside the topic of e‐cigarettes, NAR is a consultant for Achieve LifeSciences, which is developing an investigational smoking cessation medication for FDA approval (cytisine) and her institution (MGH) receives a grant from the company as a site for a clinical trial testing the safety and efficacy of cytisine. NAR holds grants from NIH for research work.

AT's work on this review has been supported by the Nuffield Department of Primary Care Health Sciences at the University of Oxford. This is not deemed a conflict of interest

TT has no known conflicts of interest.

Figures

1
1
PRISMA diagram for 2023 update
2
2
Risk of bias graph
3
3
Risk of bias summary
4
4
Funnel plot for comparison 4.4
5
5
Network map for cessation
6
6
Cessation network meta‐analysis
7
7
Network map for adverse events
8
8
Adverse events network meta‐analysis
9
9
Network map for serious adverse events
10
10
Serious adverse events network meta‐analysis
1.1
1.1. Analysis
Comparison 1: Nicotine EC versus NRT, Outcome 1: Smoking cessation
1.2
1.2. Analysis
Comparison 1: Nicotine EC versus NRT, Outcome 2: Adverse events
1.3
1.3. Analysis
Comparison 1: Nicotine EC versus NRT, Outcome 3: Serious adverse events
1.4
1.4. Analysis
Comparison 1: Nicotine EC versus NRT, Outcome 4: Carbon monoxide (ppm)
1.5
1.5. Analysis
Comparison 1: Nicotine EC versus NRT, Outcome 5: Heart rate (bpm)
1.6
1.6. Analysis
Comparison 1: Nicotine EC versus NRT, Outcome 6: Systolic blood pressure
1.7
1.7. Analysis
Comparison 1: Nicotine EC versus NRT, Outcome 7: Blood oxygen saturation
1.8
1.8. Analysis
Comparison 1: Nicotine EC versus NRT, Outcome 8: 3‐HPMA (pmol/mg creatinine)
1.9
1.9. Analysis
Comparison 1: Nicotine EC versus NRT, Outcome 9: NNAL (pmol/mg creatinine))
1.10
1.10. Analysis
Comparison 1: Nicotine EC versus NRT, Outcome 10: 2‐HPMA (pmol/mg creatinine)
1.11
1.11. Analysis
Comparison 1: Nicotine EC versus NRT, Outcome 11: HMPMA (pmol/mg creatinine)
1.12
1.12. Analysis
Comparison 1: Nicotine EC versus NRT, Outcome 12: PheT (pmol/mg creatinine)
1.13
1.13. Analysis
Comparison 1: Nicotine EC versus NRT, Outcome 13: CEMA (pmol/mg creatinine)
1.14
1.14. Analysis
Comparison 1: Nicotine EC versus NRT, Outcome 14: AAMA (pmol/mg creatinine)
1.15
1.15. Analysis
Comparison 1: Nicotine EC versus NRT, Outcome 15: FEV1
1.16
1.16. Analysis
Comparison 1: Nicotine EC versus NRT, Outcome 16: FEV1/FVC (%)
1.17
1.17. Analysis
Comparison 1: Nicotine EC versus NRT, Outcome 17: PEF (L/min)
1.18
1.18. Analysis
Comparison 1: Nicotine EC versus NRT, Outcome 18: Product use at 6+ months
2.1
2.1. Analysis
Comparison 2: Nicotine EC versus varenicline, Outcome 1: Smoking cessation
2.2
2.2. Analysis
Comparison 2: Nicotine EC versus varenicline, Outcome 2: Serious adverse events
3.1
3.1. Analysis
Comparison 3: Nicotine EC versus heated tobacco, Outcome 1: Adverse events at 12 weeks
3.2
3.2. Analysis
Comparison 3: Nicotine EC versus heated tobacco, Outcome 2: SAEs at 12 weeks
3.3
3.3. Analysis
Comparison 3: Nicotine EC versus heated tobacco, Outcome 3: Carbon monoxide (ppm) absolute values at 12 weeks
3.4
3.4. Analysis
Comparison 3: Nicotine EC versus heated tobacco, Outcome 4: VO2 Max at 12 weeks
4.1
4.1. Analysis
Comparison 4: Nicotine EC versus non‐nicotine EC, Outcome 1: Smoking cessation
4.2
4.2. Analysis
Comparison 4: Nicotine EC versus non‐nicotine EC, Outcome 2: Adverse events
4.3
4.3. Analysis
Comparison 4: Nicotine EC versus non‐nicotine EC, Outcome 3: Serious adverse events
4.4
4.4. Analysis
Comparison 4: Nicotine EC versus non‐nicotine EC, Outcome 4: Carbon monoxide (ppm)
4.5
4.5. Analysis
Comparison 4: Nicotine EC versus non‐nicotine EC, Outcome 5: Heart rate
4.6
4.6. Analysis
Comparison 4: Nicotine EC versus non‐nicotine EC, Outcome 6: Systolic blood pressure
4.7
4.7. Analysis
Comparison 4: Nicotine EC versus non‐nicotine EC, Outcome 7: FeNO (ppb)
4.8
4.8. Analysis
Comparison 4: Nicotine EC versus non‐nicotine EC, Outcome 8: FEV1 (l)
4.9
4.9. Analysis
Comparison 4: Nicotine EC versus non‐nicotine EC, Outcome 9: FEV1/FVC
4.10
4.10. Analysis
Comparison 4: Nicotine EC versus non‐nicotine EC, Outcome 10: NNAL (pmol/mg creatinine)
4.11
4.11. Analysis
Comparison 4: Nicotine EC versus non‐nicotine EC, Outcome 11: Product use at 6+ months
5.1
5.1. Analysis
Comparison 5: Nicotine EC versus behavioural support only/no support, Outcome 1: Smoking cessation
5.2
5.2. Analysis
Comparison 5: Nicotine EC versus behavioural support only/no support, Outcome 2: Adverse events
5.3
5.3. Analysis
Comparison 5: Nicotine EC versus behavioural support only/no support, Outcome 3: Serious adverse events
5.4
5.4. Analysis
Comparison 5: Nicotine EC versus behavioural support only/no support, Outcome 4: Carbon monoxide (ppm)
5.5
5.5. Analysis
Comparison 5: Nicotine EC versus behavioural support only/no support, Outcome 5: Heart rate (bpm)
5.6
5.6. Analysis
Comparison 5: Nicotine EC versus behavioural support only/no support, Outcome 6: Systolic blood pressure
5.7
5.7. Analysis
Comparison 5: Nicotine EC versus behavioural support only/no support, Outcome 7: Blood oxygen saturation
5.8
5.8. Analysis
Comparison 5: Nicotine EC versus behavioural support only/no support, Outcome 8: 3‐HPMA (SMD)
5.9
5.9. Analysis
Comparison 5: Nicotine EC versus behavioural support only/no support, Outcome 9: NNAL (SMD)
5.10
5.10. Analysis
Comparison 5: Nicotine EC versus behavioural support only/no support, Outcome 10: 2‐HPMA (pmol/mg creatinine)
5.11
5.11. Analysis
Comparison 5: Nicotine EC versus behavioural support only/no support, Outcome 11: HMPMA (pmol/mg creatinine)
5.12
5.12. Analysis
Comparison 5: Nicotine EC versus behavioural support only/no support, Outcome 12: PheT (pmol/mg creatinine)
5.13
5.13. Analysis
Comparison 5: Nicotine EC versus behavioural support only/no support, Outcome 13: CEMA (pmol/mg creatinine)
5.14
5.14. Analysis
Comparison 5: Nicotine EC versus behavioural support only/no support, Outcome 14: AAMA (pmol/mg creatinine)
5.15
5.15. Analysis
Comparison 5: Nicotine EC versus behavioural support only/no support, Outcome 15: S‐PMA (nanograms)
5.16
5.16. Analysis
Comparison 5: Nicotine EC versus behavioural support only/no support, Outcome 16: FEV1 (SMD)
5.17
5.17. Analysis
Comparison 5: Nicotine EC versus behavioural support only/no support, Outcome 17: FEF 25‐75 (litres/second))
5.18
5.18. Analysis
Comparison 5: Nicotine EC versus behavioural support only/no support, Outcome 18: PEF 25‐75 (litres/minute)
5.19
5.19. Analysis
Comparison 5: Nicotine EC versus behavioural support only/no support, Outcome 19: FEV1/FVC
6.1
6.1. Analysis
Comparison 6: Higher versus lower nicotine content, Outcome 1: Smoking cessation
6.2
6.2. Analysis
Comparison 6: Higher versus lower nicotine content, Outcome 2: Serious adverse events
6.3
6.3. Analysis
Comparison 6: Higher versus lower nicotine content, Outcome 3: Carbon monoxide (ppm)
6.4
6.4. Analysis
Comparison 6: Higher versus lower nicotine content, Outcome 4: Heart rate
6.5
6.5. Analysis
Comparison 6: Higher versus lower nicotine content, Outcome 5: Systolic blood pressure
6.6
6.6. Analysis
Comparison 6: Higher versus lower nicotine content, Outcome 6: FeNO (ppb)
6.7
6.7. Analysis
Comparison 6: Higher versus lower nicotine content, Outcome 7: FEV1 (l)
6.8
6.8. Analysis
Comparison 6: Higher versus lower nicotine content, Outcome 8: FVC (l)
6.9
6.9. Analysis
Comparison 6: Higher versus lower nicotine content, Outcome 9: FEV1/FVC
6.10
6.10. Analysis
Comparison 6: Higher versus lower nicotine content, Outcome 10: NNAL (pg/mg creatinine) at 24 weeks
6.11
6.11. Analysis
Comparison 6: Higher versus lower nicotine content, Outcome 11: Product use at 6+ months
7.1
7.1. Analysis
Comparison 7: Tobacco vs. menthol flavour, Outcome 1: Serious adverse events
7.2
7.2. Analysis
Comparison 7: Tobacco vs. menthol flavour, Outcome 2: NNAL (ng/g)
7.3
7.3. Analysis
Comparison 7: Tobacco vs. menthol flavour, Outcome 3: FEV1 (% predicted)
7.4
7.4. Analysis
Comparison 7: Tobacco vs. menthol flavour, Outcome 4: FEV1/FVC
8.1
8.1. Analysis
Comparison 8: Refillable versus cartridge, Outcome 1: Exhaled CO
9.1
9.1. Analysis
Comparison 9: Nicotine salt EC versus free‐base nicotine EC, Outcome 1: Smoking cessation
9.2
9.2. Analysis
Comparison 9: Nicotine salt EC versus free‐base nicotine EC, Outcome 2: Product use at 6+ months
10.1
10.1. Analysis
Comparison 10: Non‐nicotine EC versus behavioural support only/no support, Outcome 1: Smoking cessation
10.2
10.2. Analysis
Comparison 10: Non‐nicotine EC versus behavioural support only/no support, Outcome 2: Adverse events at 12 weeks
10.3
10.3. Analysis
Comparison 10: Non‐nicotine EC versus behavioural support only/no support, Outcome 3: Serious adverse events at 24 weeks
11.1
11.1. Analysis
Comparison 11: Non‐nicotine EC + NRT versus NRT, Outcome 1: Smoking cessation
11.2
11.2. Analysis
Comparison 11: Non‐nicotine EC + NRT versus NRT, Outcome 2: Adverse events
11.3
11.3. Analysis
Comparison 11: Non‐nicotine EC + NRT versus NRT, Outcome 3: Serious adverse events
12.1
12.1. Analysis
Comparison 12: Non‐nicotine EC versus NRT, Outcome 1: Smoking cessation
12.2
12.2. Analysis
Comparison 12: Non‐nicotine EC versus NRT, Outcome 2: Adverse events
12.3
12.3. Analysis
Comparison 12: Non‐nicotine EC versus NRT, Outcome 3: Serious adverse events
12.4
12.4. Analysis
Comparison 12: Non‐nicotine EC versus NRT, Outcome 4: Change in carbon monoxide (ppm) at 6 months
13.1
13.1. Analysis
Comparison 13: Advice to use e‐cigarettes compared to no advice to use e‐cigarettes, Outcome 1: Smoking cessation
13.2
13.2. Analysis
Comparison 13: Advice to use e‐cigarettes compared to no advice to use e‐cigarettes, Outcome 2: Adverse events at 3 months
13.3
13.3. Analysis
Comparison 13: Advice to use e‐cigarettes compared to no advice to use e‐cigarettes, Outcome 3: Serious adverse events at 3 months
13.4
13.4. Analysis
Comparison 13: Advice to use e‐cigarettes compared to no advice to use e‐cigarettes, Outcome 4: Product use at 6+ months
14.1
14.1. Analysis
Comparison 14: Nicotine EC + NRT versus non‐nicotine EC + NRT, Outcome 1: Smoking cessation
14.2
14.2. Analysis
Comparison 14: Nicotine EC + NRT versus non‐nicotine EC + NRT, Outcome 2: Adverse events
14.3
14.3. Analysis
Comparison 14: Nicotine EC + NRT versus non‐nicotine EC + NRT, Outcome 3: Serious adverse events
14.4
14.4. Analysis
Comparison 14: Nicotine EC + NRT versus non‐nicotine EC + NRT, Outcome 4: Carbon monoxide (ppm)
14.5
14.5. Analysis
Comparison 14: Nicotine EC + NRT versus non‐nicotine EC + NRT, Outcome 5: FeNO (ppb)
14.6
14.6. Analysis
Comparison 14: Nicotine EC + NRT versus non‐nicotine EC + NRT, Outcome 6: FEV1 (%)
14.7
14.7. Analysis
Comparison 14: Nicotine EC + NRT versus non‐nicotine EC + NRT, Outcome 7: FVC (%)
14.8
14.8. Analysis
Comparison 14: Nicotine EC + NRT versus non‐nicotine EC + NRT, Outcome 8: Study product use at 6+ months
15.1
15.1. Analysis
Comparison 15: Nicotine EC + NRT versus NRT, Outcome 1: Smoking cessation
15.2
15.2. Analysis
Comparison 15: Nicotine EC + NRT versus NRT, Outcome 2: Adverse events
15.3
15.3. Analysis
Comparison 15: Nicotine EC + NRT versus NRT, Outcome 3: Serious adverse events
16.1
16.1. Analysis
Comparison 16: Nicotine EC + varenicline vs. varenicline, Outcome 1: Adverse events at 12 weeks
16.2
16.2. Analysis
Comparison 16: Nicotine EC + varenicline vs. varenicline, Outcome 2: Serious adverse events at 12 weeks
See this image and copyright information in PMC

Update of

References

References to studies included in this review

Adriaens 2014 {published data only}
    1. Adriaens K, Van Gucht D, Declerck P, Baeyens F. Effectiveness of the electronic cigarette: an eight-week Flemish study with six-month follow-up on smoking reduction, craving and experienced benefits and complaints. International Journal of Environmental Research and Public Health 2014;11(11):11220-48. - PMC - PubMed
Baldassarri 2018 {published data only}
    1. Baldassarri SR, Bernstein SL, Chupp GL, Slade MD, Fucito LM, Toll BA. Electronic cigarettes for adults with tobacco dependence enrolled in a tobacco treatment program: a pilot study. Addictive Behaviors May 2018;80:1-5. - PMC - PubMed
    1. Baldassarri SR, Bernstein SL, Chupp GL, Toll BA. Electronic Cigarettes for Adults with Tobacco Dependence Undergoing a Tobacco Treatment Program: a Pilot Prospective Study,. American Journal of Respiratory and Critical Care Medicine, Meeting Abstracts 2016;193:A6511.
    1. NCT02498145. Short term effects of electronic cigarettes in tobacco dependent adults. clinicaltrials.gov/show/NCT02498145 (accessed 17 February 2016).
Begh 2021 {published data only (unpublished sought but not used)}
    1. Albury C, Barnes R, Ferrey A, Coleman T, Gilbert H, Naughton F, et al. The old and familiar meets the new and unknown: patient and clinician perceptions on e-cigarettes for smoking reduction in UK general practice, a qualitative interview study. Addiction 2021 2022 May;117(5):1427-1437. [DOI: 10.1111/add.15760] - DOI - PMC - PubMed
    1. Begh R, Bateman P, Williams N, Grabey J, Stevens R. Examining the effectiveness of general practitioner and nurse promotion of electronic cigarettes versus standard care for smoking reduction and abstinence in hardcore smokers with smoking-related chronic disease: a randomised controlled trial. Statistical Analysis Report, Version 2.0 2021:1-56. - PMC - PubMed
    1. Begh R, Coleman T, Yardley L, Barnes R, Naughton F, Gilbert H, et al. Examining the effectiveness of general practitioner and nurse promotion of electronic cigarettes versus standard care for smoking reduction and abstinence in hardcore smokers with smoking-related chronic disease: protocol for a randomised controlled trial. Trials 2019;20(1):659. - PMC - PubMed
    1. Begh R. Training general practitioners and nurses to deliver brief advice about e-cigarettes for smoking reduction: lessons learned from a randomised controlled trial. In: SRNT E-Conference, SY3-04 . 2021.
    1. ISRCTN59404712. GP/nurse promotion of e-cigarettes in supporting reduced smoking and cessation in smokers. www.isrctn.com/ISRCTN59404712 (first received 28 November 2017).
Bonafont Reyes 2022 {published data only}
    1. Bonafont Reyes BV, Stevens E, Nicholson A, Lei L, Vojjala M, Sherman S. Understanding racial and ethnic differences in switching from combustible cigarettes to e-cigarettes in COPD patients. Journal of the American Geriatrics Society, Annual Scientific Meeting 2022;170(S1):S1-S345.
Bullen 2013 {published data only}
    1. Bullen C, Howe C, Laugesen M, McRobbie H, Parag V, Williman J, et al. Electronic cigarettes and smoking cessation: a quandary? - Authors' reply. Lancet 2014;383(9915):408-9. - PubMed
    1. Bullen C, Howe C, Laugesen M, McRobbie H, Parag V, Williman J, et al. Electronic cigarettes for smoking cessation: a randomised controlled trial. Lancet 2013;382(9905):1629-37. - PubMed
    1. Bullen C, Howe C, Laugesen M, McRobbie H, Parag V, Williman J. Do electronic cigarettes help smokers quit? Results from a randomised controlled trial [Abstract]. In: European Respiratory Society Annual Congress, 2013 September 7 - 11, Barcelona, Spain. Vol. 42. 2013:215s-[P1047].
    1. Bullen C, Williman J, Howe C, Laugesen M, McRobbie H, Parag V, et al. Study protocol for a randomised controlled trial of electronic cigarettes versus nicotine patch for smoking cessation. BMC Public Health 2013;13:210. - PMC - PubMed
    1. O'Brien B, Knight-West O, Walker N, Parag V, Bullen C. E-cigarettes versus NRT for smoking reduction or cessation in people with mental illness: secondary analysis of data from the ASCEND trial. Tobacco Induced Diseases 2015;13(1):5. - PMC - PubMed
Caponnetto 2013a {published data only}
    1. Campagna D, Cibella F, Caponnetto P, Amaradio MD, Caruso M, Morjaria JB, et al. Changes in breathomics from a 1-year randomized smoking cessation trial of electronic cigarettes. European Journal of Clinical Investigation 2016;46(8):698-706. - PubMed
    1. Caponnetto P, Campagna D, Cibella F, Morjaria JB, Caruso M, Russo C, et al. EffiCiency and Safety of an eLectronic cigAreTte (ECLAT) as tobacco cigarettes substitute: a prospective 12-month randomized control design study. PlOS One 2013;8(6):e66317. - PMC - PubMed
    1. Cibella F, Campagna D, Caponnetto P, Amaradio MD, Caruso M, Russo C, et al. Lung function and respiratory symptoms in a randomized smoking cessation trial of electronic cigarettes. Clinical Science 2016;130(21):1929–37. - PubMed
    1. Farsalinos K, Cibella F, Caponnetto P, Campagna D, Morjaria JB, Battaglia E, et al. Effect of continuous smoking reduction and abstinence on blood pressure and heart rate in smokers switching to electronic cigarettes. Internal and Emergency Medicine 2016;11(1):85-94. - PMC - PubMed
    1. NCT01164072. Efficacy and safety of an electronic nicotine delivery device (e-cigarette). clinicaltrials.gov/ct2/show/NCT01164072 (first received 16 July 2010).
Caponnetto 2013b {published data only}
    1. Caponnetto P, Auditore R, Russo C, Cappello GC, Polosa R. Impact of an electronic cigarette on smoking reduction and cessation in schizophrenic smokers: a prospective 12-month pilot study. International Journal of Environmental Research and Public Health 2013;10(2):446-61. - PMC - PubMed
    1. Minutolo G, Caponnetto P, Auditore R, Russo C, Polosa R. Management of smoking reduction and cessation in inpatients with schizophrenia: Impact of electronic cigarettes. European Neuropsychopharmacology 2013;23:S581-2.
Caponnetto 2021 {published data only}
    1. Caponnetto P, DiPiazza J, Kim J, Maglia M, Polosa R. A single-arm, open-label pilot, and feasibility study of a high nicotine strength e-cigarette intervention for smoking cessation or reduction for people with schizophrenia spectrum disorders who smoke cigarettes. Nicotine & Tobacco Research 2021;23(7):1113-22. [DOI: ] - PMC - PubMed
Caponnetto 2023 {published data only}
    1. Caponnetto P, Campagna D, Maglia M, Benfatto F, Emma R, Caruso M, et al. Comparing the effectiveness, tolerability, and acceptability of heated tobacco products and refillable electronic cigarettes for cigarette substitution (CEASEFIRE): randomized controlled trial. Public Health Surveillance 2023;9:e42628. [DOI: 10.2196/42628] - DOI - PMC - PubMed
    1. Caponnetto P, Caruso M, Maglia M, Emma R, Saitta D, Busa B, et al. Non-inferiority trial comparing cigarette consumption, adoption rates, acceptability, tolerability, and tobacco harm reduction potential in smokers switching to Heated Tobacco Products or electronic cigarettes: study protocol for a randomized controlled trial. Contemporary Clinical Trials Communications 2020;8:17. - PMC - PubMed
    1. NCT03569748. Heated tobacco products vs electronic cigarettes. clinicaltrials.gov/ct2/show/NCT03569748 (first received June 25 2021).
Carpenter 2017 {published data only}
    1. Carpenter MJ, Heckman BW, Wahlquist AE, Wagener TL, Goniewicz ML, Gray KM, et al. A naturalistic, randomized pilot trial of e-cigarettes: uptake, exposure, and behavioral effects. Cancer Epidemiology, Biomarkers & Prevention 2017;26(12):1795-803. - PMC - PubMed
    1. NCT02357173. A trial of e-cigarettes: natural uptake, patterns and impact of use. clinicaltrials.gov/show/NCT02357173 (accessed 17 February 2016).
    1. Smith TT, Wahlquist AE, Heckman BW, Cummings KM, Carpenter MJ. Impact of e-cigarette sampling on cigarette dependence and reinforcement value. Nicotine & Tobacco Research 2020;22(2):297-301. - PMC - PubMed
Carpenter 2023 {published and unpublished data}
    1. Carpenter MJ, Wahlquist A, Cummings KM, Smith T. Complementary approaches to examining relationships between e-cigarettes and smoking: novel data from the US. In: SRNT 29th Annual Meeting; 2023 Mar 1-4; San Antonio (TX), USA. SYM5-1. 2023:5-6.
    1. NCT03453385. Clinical Outcomes of a Nationwide, Naturalistic E-Cig Trial (CONNECT). clinicaltrials.gov/ct2/show/NCT03453385 (first received 5 March 2018).
    1. O'Neal R, Fahey MC, Wahlquist A, Smith T, Carpenter M. Demographic and smoking history correlates of anticipated reasons for ENDS use. In: SRNT 29th Annual Meeting; 2023 Mar 1-4; San Antonio (TX), USA. POS2-18. 2023:121.
Cobb 2021 {published and unpublished data}
    1. Cobb CO, Foulds J, Yen M-S, Veldheer S, Lopez AA, Yingst JM et al. Effect of an electronic nicotine delivery system with 0, 8, or 36 mg/mL liquid nicotine versus a cigarette substitute on tobacco-related toxicant exposure: a four-arm, parallel-group, randomised, controlled trial. Lancet Respiratory Medicine April 2021;9(8):840-50. [DOI: org/10.1016/ S2213-2600(21)00022-9] - PMC - PubMed
    1. Foulds J, Cobb C, Yen M-S, Veldheer S, Brosnan P, Yingst J et al. Effect of electronic nicotine delivery systems on cigarette abstinence in smokers with no plans to quit: exploratory analysis of a randomized placebo-controlled trial. Nicotine Tobacco Research 2022 Jun 15;24(7):955-961. [DOI: 10.1093/ntr/ntab247] - DOI - PMC - PubMed
    1. Lopez AA, Cobb CO, Yingst JM, Veldheer S, Hrabovsky S, Yen MS, et al. A transdisciplinary model to inform randomized clinical trial methods for electronic cigarette evaluation. BMC Public Health 2016;16(1):217. [PMCID:: PMC4778292] [PMID: ] - PMC - PubMed
    1. NCT02342795. Randomized controlled trial methods for novel tobacco products evaluation. clinicaltrials.gov/show/NCT02342795 (accessed 17 February 2016).
    1. Veldheer S, Yingst J, Midya V, Hummer B, Lester C, Krebs N, . Pulmonary and other health effects of electronic cigarette use among adult smokers participating in a randomized controlled smoking reduction trial. Addictive Behaviors 2019;91:95-101. - PMC - PubMed
Coffey 2020 {published data only}
    1. Coffey M, Cooper-Ryan AM, Houston L, Thompson K, Cook PA. Using e-cigarettes for smoking cessation: evaluation of a pilot project in the North West of England. Perspectives in Public Health 2020 Nov;140(6):351-61. [DOI: 10.1177/1757913920912436] - DOI - PMC - PubMed
Czoli 2019 {published and unpublished data}
    1. Czoli CD, Fong GT, Goniewicz ML, Hammond D. Biomarkers of exposure among "dual users" of tobacco cigarettes and electronic cigarettes in Canada. Nicotine and Tobacco Research 2019;21(9):1259-66. - PMC - PubMed
Dawkins 2020 {published and unpublished data}
    1. Dawkins L, Bauld L, Ford A, Robson D, Hajek P, Parrott S, et al. A cluster feasibility trial to explore the uptake and use of e-cigarettes versus usual care offered to smokers attending homeless centres in Great Britain. PLOS One 2020;15(10):e0240968. [ISRCTN14140672] - PMC - PubMed
    1. ISRCTN14140672. Exploring the use and uptake of e-cigarettes for homeless smokers. www.isrctn.com/ISRCTN14140672 (first received 7 November 2018).
Edmiston 2022 {published data only}
    1. Edmiston JS, Webb KM, Wang J, Oliveri D, Liang Q, Sarkar M. Biomarkers of exposure and biomarkers of potential harm in adult smokers who switch to e-vapor products relative to cigarette smoking in a 24-week, randomized, clinical trial. Nicotine & Tobacco Research 2022;24(7):1047–54. [DOI: ] - PMC - PubMed
Edwards 2023 {published and unpublished data}
    1. ACTRN12616001641482. Tobacco harm reduction with vaporised nicotine (THRiVe): feasibility study. www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12616001641482 (first received 28 November 2016).
    1. Bell S, Dean J, Gilks C, Boyd MA, Fitzgerald L, Mutch A, et al. Tobacco harm reduction with vaporised nicotine (THRiVe): the study protocol of an uncontrolled feasibility study of novel nicotine replacement products among people living with HIV who smoke. International Journal of Environmental Research and Public Health 2017;14(7):799. - PMC - PubMed
    1. Edwards S, Puljevic C, Dean JA, Gilks C, Boyd MA, Baker P, et al. Tobacco harm reduction with vaporised nicotine (THRiVe): a feasibility trial of nicotine vaping products for smoking cessation among people living with HIV. AIDS and Behavior 2023;27(2):618-27. [DOI: 10.1007/s10461-022-03797-0] - DOI - PMC - PubMed
Eisenberg 2020 {published data only}
    1. Eisenberg MJ, Hébert-Losier M, Windle SB, Greenspoon T, Brandys T, Fülöp T. Effect of e-cigarettes plus counseling vs counseling alone on smoking cessation: a randomized clinical trial. JAMA 2020;324(18):1844-54. - PMC - PubMed
    1. Hebert-Losier A, Filion KB, Windle SB, Eisenberg MJ. A randomized controlled trial evaluating the efficacy of e-cigarette use for smoking cessation in the general population: E3 trial design. Canadian Journal of Cardiology Open 2020;2(3):168-75. [NCT02417467] - PMC - PubMed
    1. NCT02417467. Evaluating the efficacy of e-cigarette use for smoking cessation (E3) trial. clinicaltrials.gov/show/NCT02417467 (accessed 17 February 2016).
Eisenhofer 2015 {published data only}
    1. Eisenhofer J, Makanjuola T, Martinez V, Thompson-Lake DG, Rodgman C, DeBrule DS, et al. Efficacy of electronic cigarettes for smoking cessation in veterans. Drug and Alcohol Dependence 2015;156:e63-e64.
Elling 2023 {published data only}
    1. Elling JM, Crutzen R, Talhout R, DeVries H. Effects of providing tailored information about e-cigarettes in a web-based smoking cessation intervention: protocol for a randomised control trial. Journal of Medical Internet Research, Research Protocols 2021;10(5):e27088. [DOI: 10.2196/27088] - DOI - PMC - PubMed
    1. Elling JM, Crutzen R, Talhout R, Vries H. Effects of providing tailored information about e-cigarettes in a digital smoking cessation intervention: randomized controlled trial. Health Education Research 2023;38(2):150-162. [DOI: 10.1093/her/cyad004] - DOI - PMC - PubMed
    1. NL8330. Communication about e-cigarettes in a digital smoking cessation intervention [Effect of communication about e-cigarettes in a digital smoking cessation intervention on smoking reduction, smoking cessation, and informed decision making]. trialsearch.who.int/?TrialID=NL8330 (first received 24 January 2020).
Ely 2013 {published data only}
    1. Ely J. Evaluation of the use of electric cigarettes in a rural smoking cessation program. Available online at: digscholarship.unco.edu/cgi/viewcontent.cgi?article=1001&context=cap... 2013 (accessed 1st November 2014).
ESTxENDS Trial {published data only}
    1. Auer R, Schoeni A, Humair JP, Jacot-Sadowski I, Berlin I, Stuber M, et al. Efficacy, safety and toxicology of electronic nicotine delivery systema (ESTXENDS) as an aid for smoking cessation, a randomised controlled trial. In: SRNT 29th Annual Meeting; 2023 Mar 1-4; San Antonio (TX), USA. POS3-5. 2023.
    1. Güttinger E, Mosimann A, Tal K, Schoeni A, Jacot-Sadowski I, Humair JP, et al. Prevalence of vaping-associated symptoms over six months among participants of a randomized controlled trial on smoking cessation with electronic nicotine delivery systems (ENDS). In: SRNT 29th Annual Meeting; 2023 Mar 1-4; San Antonio (TX), USA. PPS14-6. 2023.
    1. Jakob J, Schoeni A, Tal K, Jacot-Sadowski I, Clair C, Humair JP, et al. Effects of electronic nicotine delivery systems (ENDS) for smoking cessation on changes in weight- secondary analysis of the ESTXENDS trial. In: SRNT 29th Annual Meeting; 2023 Mar 1-4; San Antonio (TX), USA. POS3-8. 2023.
    1. Mosimann AF, Güttinger EM, Tal K, Baggio S, Schoeni A, Jacot-Sadowski I, et al. Change in e-liquids flavor use and nicotine concentration over 6 months in participants of a smoking cessation trial with electronic nicotine delivery systems (ENDS): the ESTxENDS Trial. In: SRNT 29th Annual Meeting; 2023 Mar 1-4; San Antonio (TX), USA. PPS10-5. 2023:46.
    1. NCT03589989. The ESTxENDS trial - electronic nicotine delivery systems (ENDS/vaporizer/e-cigarette) as an aid for smoking cessation (ESTxENDS). clinicaltrials.gov/ct2/show/record/NCT03589989 (first received 18 July 2018).
Felicione 2019 {published data only}
    1. Felicione NJ, Enlow P, Elswick D, Long D, Sullivan CR, Blank MD. A pilot investigation of the effect of electronic cigarettes on smoking behavior among opioid-dependent smokers. Addictive Behaviors 2019;91:45-50. - PubMed
George 2019 {published data only}
    1. George J, Hussain M, Vadiveloo T, Ireland S, Hopkinson P, Struthers AD, et al. Cardiovascular effects of switching from tobacco cigarettes to electronic cigarettes. Journal of the American College of Cardiology 2019;74(25):3112-20. - PMC - PubMed
    1. NCT02878421. Vascular EffectS of regUlar cigarettes Versus electronIc cigarette USe (VESUVIUS). clinicaltrials.gov/ct2/show/NCT02878421 (first received 25 August 2016).
Goniewicz 2017 {published data only}
    1. Goniewicz ML, Gawron M, Smith DM, Peng M, Jacob P 3rd, Benowitz NL. Exposure to nicotine and selected toxicants in cigarette smokers who switched to electronic cigarettes: a longitudinal within-subjects observational study. Nicotine & Tobacco Research 2017;19(2):160-7. - PMC - PubMed
Guillaumier 2018 {unpublished data only}
    1. ACTRN12617000849392. The QuitNic Study: a pilot study of electronic nicotine devices for smoking cessation with drug and alcohol clients. www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=372198 (first received 8 June 2017).
    1. Bonevski B, Manning V, Wynne O, Gartner C, Borland R, Baker A, et al. QuitNic: A pilot randomised controlled trial comparing nicotine vaping products with nicotine replacement therapy for smoking cessation following residential detoxification. Nicotine and Tobacco Research 2021;23(3):462-70. - PMC - PubMed
    1. Guillaumier A, Manning V, Wynne O, Gartner C, Borland R, Baker AL, et al. Electronic nicotine devices to aid smoking cessation by alcohol- and drug-dependent clients: protocol for a pilot randomised controlled trial. Trials 2018;19:415. - PMC - PubMed
Hajek 2015a {published data only}
    1. Hajek P, Corbin L, Ladmore D, Spearing E. Adding e-cigarettes to specialist stop-smoking treatment: City of London pilot project. Journal of Addiction Research & Therapy 2015;6(244):(online ahead of print). [DOI: 10.4172/2155-6105.1000244] - DOI
Hajek 2019 {published and unpublished data}ISRCTN60477608
    1. Hajek P, Phillips-Waller A, Przulj D, Pesola F, Myers Smith K, Bisal N, et al. A randomized trial of e-cigarettes versus nicotine-replacement therapy. New England Journal of Medicine 2019;380(7):629-37. - PubMed
    1. Hajek P, Phillips-Waller A, Przulj D, Pesola F, Smith KM, Bisal N, et al. E-cigarettes compared with nicotine replacement therapy within the UK Stop Smoking Services: the TEC RCT. Health Technology Assessment 2019;23(43):1-82. [ISRCTN60477608] - PMC - PubMed
    1. ISRCTN60477608. The efficacy of e-cigarettes compared with nicotine replacement therapy, when used within the UK stop smoking service. www.isrctn.com/ISRCTN60477608 2014 (first received 2 April 2015).
    1. Li J, Hajek P, Pesola F, Wu Q, Phillips-Waller A, Przulj D, et al. Cost-effectiveness of e-cigarettes compared with nicotine replacement therapy in stop smoking services in England (TEC study): a randomized controlled trial. Addiction 2020;115(3):507-17. - PMC - PubMed
Hajek 2022 {published and unpublished data}
    1. Ford A, Uny I, Lowes J, Naughton F, Cooper S, Coleman T. A qualitative study of factors influencing adherence among pregnant women taking part in a trial of e-cigarettes for smoking cessation. International Journal of Environmental Research and Public Health 2021;18(2):430. - PMC - PubMed
    1. Hajek P, Przulj D, Pesola F, Griffiths C, Walton R, McRobbie H, et al. Author Correction: Electronic cigarettes versus nicotine patches for smoking cessation in pregnancy: a randomized controlled trial. Nature Medicine 2022;Nov 7:Epub. [DOI: 10.1038/s41591-022-02099-1] - DOI - PMC - PubMed
    1. Hajek P, Przulj D, Pesola F, Griffiths C, Walton R, McRobbie H, et al. Electronic cigarettes versus nicotine patches for smoking cessation in pregnancy: a randomized controlled trial. Nature Medicine 2022;28:958-64. [DOI: ] - PMC - PubMed
    1. ISRCTN62025374. Helping pregnant smokers quit: a multi-centre study of electronic cigarettes and nicotine patches. www.isrctn.com/ISRCTN62025374 (first received March 21 2017). [DOI: ]
Halpern 2018 {published data only}
    1. Halpern SD, Harhay MO, Saulsgiver K, Brophy C, Troxel AB, Volpp KG. A pragmatic trial of e-cigarettes, incentives, and drugs for smoking cessation. New England Journal of Medicine 2018;378(24):2302-10. - PubMed
    1. Harhay MO, Troxel AB, Brophy C, Saulsgiver K, Volpp KG, Halpern SD, . Financial incentives promote smoking cessation directly, not by increasing use of cessation aids. Annals of the American Thoracic Society 2019 February;16(2):280-282. [DOI: 10.1513/AnnalsATS.201808-574RL] - DOI - PMC - PubMed
    1. NCT02328794. Randomized clinical trial to reduce harm from tobacco. clinicaltrials.gov/show/NCT02357173 (accessed 17 February 2016).
Hatsukami 2020 {published and unpublished data}
    1. Hatsukami D, Meier E, Lindgren BR, Anderson A, Reisinger S, Norton K, et al. A randomized clinical trial examining the effects of instructions for electronic cigarette use on smoking-related behaviors, and biomarkers of exposure. Nicotine & Tobacco Research 2020;22(9):1524-32. [DOI: 10.1093/ntr/ntz233] - DOI - PMC - PubMed
    1. NCT03111537. Methods project 4: clinical trial - amended (COMET). https://clinicaltrials.gov/ct2/show/NCT03111537 (Accessed 10 September 2022).
Hickling 2019 {published data only}
    1. Hickling LM, Perez-Iglesias R, McNeill A, Dawkins L, Moxham J, Ruffell T, et al. A pre-post pilot study of electronic cigarettes to reduce smoking in people with severe mental illness. Psychological Medicine 2019;49(6):1033-40. - PubMed
    1. NCT02212041. Acceptability, patterns of use and safety of electronic cigarette in people with mental illness: a pilot study. clinicaltrials.gov/show/NCT02212041 (accessed 17 February 2016).
Holliday 2019 {published data only}
    1. Holliday R, Preshaw PM, Ryan V, Sniehotta FF, McDonald S, Bauld L, et al. A feasibility study with embedded pilot randomised controlled trial and process evaluation of electronic cigarettes for smoking cessation in patients with periodontitis. Pilot and Feasibility Studies 2019;5:74. - PMC - PubMed
    1. Holliday et al. E-cigarettes for smoking cessation in patients with periodontitis: pilot RCT. In: IADR International Association for Dental Research. 2019.
    1. ISRCTN17731903. Feasibility study of e-cigarettes in periodontitis. www.isrctn.com/ISRCTN17731903 (first received 27 September 2016).
Humair 2014 {published data only}
    1. Humair J-P, Tango R. Can e-cigarette help patients to reduce or stop smoking in primary care practice? Journal of General Internal Medicine 2014;29:S480.
Ikonomidis 2018 {published data only}
    1. Ikonomidis I, Vlastos D, Kourea K, Kostelli G, Varoudi M, Pavlidis G, et al. Electronic cigarette smoking increases arterial stiffness and oxidative stress to a lesser extent than a single conventional cigarette: an acute and chronic study. Circulation 2018;137(3):303-6. - PubMed
    1. NCT03039920. The effects of electronic cigarette smoking on the arterial wall and endothelial glycocalyx properties of smokers. clinicaltrials.gov/ct2/show/NCT03039920 (first received 1 February 2017).
Ikonomidis 2020a {published data only}
    1. Ikonomidis I, Katogiannis K, Kostelli G, Kourea K, Kyriakou E, Kypraiou A, et al. Effects of electronic cigarette on platelet and vascular function after four months of use. Food and Chemical Toxicology 2020;141:111389. - PubMed
Ikonomidis 2020b {published and unpublished data}
    1. Ikonomidis I, Katogiannis K, Kostelli G, Kourea K, Kyriakou E, Kypraiou A, et al. Effects of electronic cigarette on platelet and vascular function after one month of use. In: European Heart Journal 2020; Conference: European Society of Cardiology Congress, ESC 2020. Suppl 2 edition. Vol. 41. 2020:2359.
Ioakeimidis 2018 {published data only}
    1. Ioakeimidis N, Vlachopoulos C, Georgakopoulos C, Abdelrasoul M, Skliros N, Katsi V, et al. Smoking cessation rates with varenicline and electronic cigarettes in relapsed smokers with a history of acute coronary syndrome. European Heart Journal 2018;39(Suppl_1):242.
Kanobe 2022 {published data only}
    1. Kanobe MN, Jones BA, Nelson P, Brown BG, Chen P, Makena P, et al. Part three: a randomized study to assess biomarker changes in cigarette smokers switched to Vuse Solo or abstinence. Scientific Reports 2022;12:20658. [DOI: ] - PMC - PubMed
    1. NCT03170674. CSD170501: Study to assess biomarkers of tobacco exposure in smokers during In-clinic confinement switch to an electronic cigarette. clinicaltrials.gov/ct2/show/NCT03170674 (first received 31 May 2017).
Kerr 2020 {published and unpublished data}
    1. Kerr D. Chapter 5: A randomised controlled trial investigating the cardiovascular effects of e-cigaretttes in comparison to nicotine replacement patches [personal communication]. Studies into the Cardiovascular and Respiratory Effects of Electronic Cigarettes (PhD thesis), emailed to: A Butler 27 September 2020.
    1. NCT03358953. The cardiovascular impacts of electronic cigarettes in comparison to the use of nicotine replacement patches (VAPOUR). clinicaltrials.gov/ct2/show/NCT03358953 (first received December 2 2017 ).
Kimber 2021 {published data only}
    1. Kimber CF, Soar K, Dawkins LE. Changes in puffing topography and subjective effects over a 2-week period in e-cigarette naive smokers: effects of device type and nicotine concentrations. Addictive Behaviors 2021;118:106909. [DOI: 10.1016/j.addbeh.2021.106909] - DOI - PubMed
Klonizakis 2022 {published data only}
    1. Jones G, McIntosh E, Brose LS, Klonizakis M. Participant experiences of a quit smoking attempt through either Nicotine Replacement Therapy (NRT) methods or the use of an e-cigarette. Journal of Addiction Medicine 2022;16(3):272-7. - PubMed
    1. Klonizakis M, Crank H, Gumber A, Brose LS. Smokers making a quit attempt using e-cigarettes with or without nicotine or prescription nicotine replacement therapy: impact on cardiovascular function (ISME-NRT) - a study protocol. BMC Public Health 2017;17(1):293. - PMC - PubMed
    1. Klonizakis M, Gumber A, McIntosh E, Brose LS. Medium-and longer-term cardiovascular effects of e-cigarettes in adults making a stop-smoking attempt: a randomized controlled trial. BMC Medicine 2022;20(1):276. [DOI: ] - PMC - PubMed
    1. Klonizakis M, Gumber A, McIntosh E, Brose LS. Short-term cardiovascular effects of e-cigarettes in adults making a stop-smoking attempt: a randomized controlled trial. Biology 2021;10(11):1208. [DOI: 10.3390/biology10111208] - DOI - PMC - PubMed
    1. NCT03061253. E-cigarettes and cardiovascular function (ISME-NRT). clinicaltrials.gov/ct2/show/NCT03061253 (first received 23 February 2017).
Kumral 2016 {published data only}
    1. Kumral TL, Saltürk Z, Yildirim G, Uyar Y, Berkiten G, Atar Y, et al. How does electronic cigarette smoking affect sinonasal symptoms and nasal mucociliary clearance? B-ENT 2016;12(1):17-21. - PubMed
Lee 2018 {published data only}
    1. Lee SM, Tenney R, Wallace A, Arjojmandi M. The end perioperative smoking pilot study: a randomized trial comparing e-cigarettes versus nicotine patch. Canadian Journal of Anesthesia 2017;64(1 Supplement 1):S48-S49.
    1. Lee SM, Tenney R, Wallace A, Arjomandi M. Exploring the teachable moment: facilitators and barriers to perioperative smoking cessation, a qualitative study,. Canadian Journal of Anesthesia 2017; Conference: 2017 Annual Meeting of the Canadian Anesthesiologists' Society, Canada. 61;1 Supplement:S46-S47.
    1. Lee SM, Tenney R, Wallace AW, Arjomandi M. E-cigarettes versus nicotine patches for perioperative smoking cessation: a pilot randomized trial. PeerJ 2018;6(9):e5609. - PMC - PubMed
    1. NCT02482233. A pilot randomized controlled clinical trial - "Electronic nicotine delivery device (e-cigarette) for perioperative smoking cessation in veterans". clinicaltrials.gov/show/NCT02482233 (accessed 17 February 2016).
Lee 2019 {published data only}
    1. KCT0001277. Effect of an electronic cigarette for smoking reduction and cessation in Korean male smokers: a randomized, controlled study. KCT0001277 2014 (accessed 15 August 2016). - PubMed
    1. Lee SH, Ahn SH, Cheong YS. Effect of electronic cigarettes on smoking reduction and cessation in Korean male smokers: a randomized controlled study. Journal of the American Board of Family Medicine 2019;32(4):567-74. - PubMed
Lucchiari 2022 {published data only}
    1. Lucchiari C, Masiero M, Mazzocco K, Veronesi G, Maisonneauve P, Jemos C, et al. Benefits of e-cigarettes in smoking reduction and in pulmonary health among chronic smokers undergoing a lung cancer screening program at 6 months. Addictive Behaviours 2020;103:106222. - PubMed
    1. Lucchiari C, Masiero M, Mazzocco K, Veronesi G, Maisonneuve P, Jemos C et al. Nicotine-Free E-Cigarettes Might Promote Tobacco Smoking Reduction Better Than Nicotine Delivery Devices: Results of a Double-Blind Randomized Controlled Trial at 1 Year. Current Oncology (Toronto, Ont.) 2022;29(11):8579-90. - PMC - PubMed
    1. Lucchiari C, Masiero M, Mazzocco K, Veronesi G, Maisonneuve P, Jemos C, et al. Nicotine-free e-cigarettes might promote tobacco smoking reduction better than nicotine delivery devices: results of a double-blind randomized controlled trial at 1 year. Current Oncology 2022;29(11):8579-90. [DOI: 10.3390/curroncol29110676] - DOI - PMC - PubMed
    1. Lucchiari C, Masiero M, Veronesi G, Maisonneuve P, Spina S, Jemos C, et al. Benefits of e-cigarettes among heavy smokers undergoing a lung cancer screening program: randomized controlled trial protocol. JMIR Research Protocols 2016;5(1):e21. [PMID: ] - PMC - PubMed
    1. Masiero M, Lucchiari C, Mazzocco K, Veronesi G, Maisonneuve P Jemos C, et al. Corrigendum: E-cigarettes may support smokers with high smoking-related risk awareness to stop smoking in the short run: preliminary results by randomized controlled trial. Nicotine and Tobacco Research 2020;22(4):594-5. [NCT02422914] - PubMed
Martinez 2021 {published data only}
    1. Byrne M, Simmons V, Martinez U, Sutton S, Brandon K, Brandon T. Cost effectiveness of a smoking cessation intervention for dual users of combustible and electronic cigarettes. In: Society for Research on Nicotine and Tobacco, Annual Meeting, Baltimore USA. March 2022.
    1. Gore LR, Sutton SK, Martinez U, Brandon KO, Simmons VN, Brandon TH. Mediators of initial abstinence for an extended self help smoking cessation intervention with dual users of combustible and electronic cigarettes. In: Society for Research on Nicotine and Tobacco, Annual Meeting, Baltimore USA. Vol. PS3-7. March 2022.
    1. Martinez U, Simmons VN, Brandon KO, Quinn GP, Brandon TH. Examining smoking and vaping behaviors, expectancies, and cessation outcomes between bisexual and heterosexual individuals. Behavioral Medicine 2023;49(4):392-401. [DOI: 10.1080/08964289.2022.2077295] - DOI - PMC - PubMed
    1. Martinez U, Simmons VN, Sutton SK, Drobes DJ, Meltzer LR, Brandon KO, et al. Targeted smoking cessation for dual users of combustible and electronic cigarettes: a randomised controlled trial. Lancet Public Health 2021;6(7):e500-9. - PMC - PubMed
    1. Meltzer LR, Simmons VN, Sutton SK, Drobes DJ, Quinn GP, Meade CD, et al. A randomized controlled trial of a smoking cessation self-help intervention for dual users of tobacco cigarettes and e-cigarettes: intervention development and research design. Contemporary Clinical Trials 2017;60:56-62. - PMC - PubMed
Martner 2019 {published data only (unpublished sought but not used)}
    1. Martner SG, Dallery J. Technology-based contingency management and e-cigarettes during the initial weeks of a smoking quit attempt. Journal of Applied Behavior Analysis 2019;52(4):928-43. - PMC - PubMed
McRobbie 2015 {published data only}
    1. McRobbie H, Goniewicz M, Phillips A, Myers-Smith K, West O, Hajek P. Effects of the use of electronic cigarettes with and without concurrent smoking on acrolein delivery POS4-33. In: Society for Research on Nicotine and Tobacco, 20th Annual Meeting, Seattle, Washington. 2014:13. [www.srnt.org/conferences/2014/pdf/SRNT_2014_Rapids_C.pdf]
    1. McRobbie H, Phillips A, Goniewicz ML, Smith KM, Knight-West O, Przulj D, et al. Effects of switching to electronic cigarettes with and without concurrent smoking on exposure to nicotine, carbon monoxide, and acrolein. Cancer Prevention Research (Philadelphia, Pa.) 2015;8(9):873-8. - PubMed
    1. NCT01714778. Toxins and Delivery in E-cigarette USers (TADEUS). clinicaltrials.gov/ct2/show/NCT01714778 (first received 26 October 2012).
Meier 2017 {published data only}
    1. Meier E, Wahlquist AE, Heckman BW, Cummings KM, Froeliger B, Carpenter MJ. A pilot randomized crossover trial of electronic cigarette sampling among smokers. Nicotine & Tobacco Research 2017;19(2):176-82. - PMC - PubMed
Morphett 2022a {unpublished data only}
    1. ACTRN12612001210864. Can using nicotine as a long-term substitute enhance smoking cessation over using it only as a cessation aid? [An open-label randomised pragmatic policy trial examining effectiveness of short-term use of Nicotine Replacement Therapy (NRT) vs short- or long-term use of NRT vs short- or long-term use of NRT or electronic nicotine delivery systems for smoking cessation in cigarette smokers.]. https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=1261... (first received November 15 2012).
    1. Fraser D, Borland R, Gartner C. Protocol for a randomised pragmatic policy trial of nicotine products for quitting or long-term substitution in smokers. BMC Public Health 2015;15:1026. - PMC - PubMed
    1. Morphett K, Fraser D, Borland R, Hall W, Walker N, Bullen C, et al. A pragmatic randomized comparative trial of e-cigarettes and other nicotine products for quitting or long-term substitution in smokers. Nicotine & Tobacco Research 2022;24(7):1079-88. [DOI: doi: 10.1093/ntr/ntab266] - PubMed
Morphett 2022b {published and unpublished data}
    1. ACTRN12618000408280. Cessation And Relapse Prevention (CARP) trial: nicotine vaporisers compared to standard nicotine replacement therapy for smoking cessation among people with co-morbidities. www.anzctr.org.au/ACTRN12618000408280.aspx (first received 21 March 2018).
    1. Morphett K, Boyd M, Puljevic C, Gilks C, Bonevski B, Borland R, et al. Do nicotine vaping products increase quitting among priority population groups over standard smoking cessation therapy? A pragmatic randomised partial cross-over trial. In: Society for Research on Nicotine and Tobacco (SRNT), Annual Meeting 2022. Vol. SYM17-4. 2022.
Morris 2022 {published data only}
    1. Morris P, McDermott S, Chapman F, Verron T, Cahours X, Stevenson M, et al. Reductions in biomarkers of exposure to selected harmful and potentially harmful constituents following exclusive and partial switching from combustible cigarettes to myblu TM electronic nicotine delivery systems (ENDS). Internal & Emergency Medicine 2022;17(2):397-410. [DOI: 10.1007/s11739-021-02813-w] - DOI - PMC - PubMed
    1. NCT04429932. A study to evaluate nicotine uptake and biomarkers in adult smokers using mybluTM electronic cigarettes. clinicaltrials.gov/ct2/show/NCT04429932 (first received June 7 2021).
    1. NCT04430634. A study to evaluate nicotine uptake and biomarkers in smokers using mybluTM electronic cigarettes [An open-label, randomized, crossover study to assess nicotine uptake, tobacco-related biomarkers of exposure, biomarkers of potential harm, and puff topography with use of mybluTM electronic cigarettes in adult smokers]. clinicaltrials.gov/ct2/show/NCT04430634 (first received June 7 2021).
Myers‐Smith 2022 {published data only}
    1. ISRCTN13288677. Can electronic cigarettes and nicotine replacement treatment help reduce smoking in smokers who struggle to quit? www.isrctn.com/ISRCTN13288677 (first received 17 March 2017).
    1. Myers Smith K, Phillips-Waller A, Pesola F, McRobbie H, Przulj D, Orzol M, et al. E-cigarettes versus nicotine replacement treatment as harm reduction interventions for smokers who find quitting difficult: randomised controlled trial. Addiction 2022;117(1):224-33. [DOI: ] - PubMed
NCT02648178 {published data only}
    1. NCT02648178. Evaluation of appeal and impact of e-cigarettes among chronic smokers with smoking-related cancers. clinicaltrials.gov/show/NCT02648178 (accessed 17 February 2016).
NCT02918630 {published data only}
    1. NCT02918630. E-cigarettes to promote smoking reduction among individuals with schizophrenia. clinicaltrials.gov/ct2/show/NCT02918630 (first received 5 July 2018).
NCT03492463 {published data only}
    1. NCT03492463. The role of nicotine dose and route of delivery in affecting adoption of e-cigarettes and reducing exposure to toxic combustion products (ENDS-Switch). clinicaltrials.gov/ct2/show/study/NCT03492463 (first received April 10 2018).
NCT04084210 {published data only}
    1. NCT04084210. Impact of alternative nicotine-delivery products on combustible cigarette use [Understanding the real-world impact of the use of three alternate nicotine-delivery products on combustible cigarette use]. clinicaltrials.gov/ct2/show/NCT04084210 (first received September 10, 2019).
    1. Piper M, Schlam T, Donny E, Jorenby D. The real-world impact of three alternative nicotine delivery products on combustible cigarette use. In: Society for Research on Nicotine and Tobacco (SRNT) 29th Annual Meeting 1-4 March 2023. Vol. SYM17-2. 2023:p 22.
Nides 2014 {published data only}
    1. NCT01898169. Evaluation of short-term safety and use patterns of an electronic nicotine delivery system. clinicaltrials.gov/ct2/show/NCT01898169 (first received 12 July 2013).
    1. Nides MA, Leischow SJ, Bhatter M, Simmons M. Nicotine blood levels and short-term smoking reduction with an electronic nicotine delivery system. American Journal of Health Behavior 2014;38(2):265-74. - PubMed
Okuyemi 2022 {published data only}
    1. NCT03084315. Changes in biomarkers associated with use of electronic cigarettes [Changes in biomarkers associated with use of electronic cigarettes among African American menthol and non-menthol smokers]. clinicaltrials.gov/ct2/show/NCT03084315 (first received March 20 2017).
    1. Okuyemi KS, Ojo-Fati O, Aremu TO, Friedrichsen CS, Grude L, Oyenuga M, et al. A randomized trial of nicotine vs. no-nicotine e-cigarettes among African American smokers: changes in smoking and tobacco biomarkers. Nicotine & Tobacco Research 2022;24(4):555-63. [DOI: ] - PubMed
Oncken 2015 {published data only}
    1. NCT01775787. Effects of Electronic Cigarettes on Nicotine Concentrations (ECIG). clinicaltrials.gov/ct2/show/NCT01775787 (first received 25 January 2013).
    1. Oncken CA, Litt MD, McLaughlin LD, Burki NA. Nicotine concentrations with electronic cigarette use: effects of sex and flavor. Nicotine & Tobacco Research 2015;17(4):473-8. - PubMed
    1. Swedeh MA, Oncken C, Burki NK. Acute effects of electronic cigarettes on airway function in human subjects. In: American Thoracic Society International Conference Abstracts. Vol. 189. 2014:A4089.
Ozga‐Hess 2019 {published data only}
    1. Ozga-Hess JE, Felicione NJ, Ferguson SG, Dino G, Elswick D, Whitworth C, et al. Piloting a clinical laboratory method to evaluate the influence of potential modified risk tobacco products on smokers' quit-related motivation, choice, and behaviour. Addictive Behaviors 2019;99:106105. - PMC - PubMed
Pacifici 2015 {published data only}
    1. Pacifici R, Pichini S, Graziano S, Pellegrini M, Massaro G, Beatrice F. Successful nicotine intake in medical assisted use of e-cigarettes: a pilot study. International Journal of Environmental Research and Public Health 2015;12(7):7638-46. - PMC - PubMed
Polosa 2011 {published data only}
    1. NCT01195597. Smoking cessation and reduction with an electronic nicotine delivery device (ENDD). clinicaltrials.gov/ct2/show/NCT01195597 (first received 6 September 2010).
    1. Polosa R, Caponnetto P, Morjaria JB, Papale G, Campagna D, Russo C. Effect of an electronic nicotine delivery device (e-cigarette) on smoking reduction and cessation: a prospective 6-month pilot study. BMC Public Health 2011;11:786. - PMC - PubMed
    1. Polosa R, Morjaria JB, Caponnetto P, Campagna D, Russo C, Alamo A, et al. Effectiveness and tolerability of electronic cigarette in real-life: a 24-month prospective observational study. Internal and Emergency Medicine 2014;9(5):537-46. - PubMed
Polosa 2014b {published data only}
    1. NCT02124200. High cessation rates in smokers using personal vaporizers (VAPECIG). clinicaltrials.gov/ct2/show/NCT02124200 (first received 28 April 2014).
    1. Polosa R, Caponnetto P, Maglia M, Morjaria JB, Russo C. Success rates with nicotine personal vaporizers: a prospective 6-month pilot study of smokers not intending to quit. BMC Public Health 2014;14:1159. - PMC - PubMed
Polosa 2015 {published data only}
    1. Polosa R, Caponnetto P, Cibella F, Le-Houezec J. Quit and smoking reduction rates in vape shop consumers: a prospective 12-month survey. International Journal of Environmental Research and Public Health 2015;12(4):3428-38. - PMC - PubMed
Pratt 2016 {published data only}
    1. Pratt SI, Sargent J, Daniels L, Santos MM, Brunette M. Appeal of electronic cigarettes in smokers with serious mental illness. Addictive Behaviors 2016;59:30-4. - PubMed
Pratt 2022 {published and unpublished data}
    1. NCT03050853. The appeal and impact of e-cigarettes in smokers with SMI. clinicaltrials.gov/ct2/show/NCT03050853 (first received February 13 2017).
    1. Pratt S, Ferron J, Sargent J, Brunette M. Assessing the effect of e-cigarettes versus usual smoking on NNAL among chronic smokers with serious mental illness. In: Society for Research on Nicotine and Tobacco (SRNT) 29th Annual Meeting 1-4 March 2023 . Vol. PPS22-5. 2023:p73.
    1. Pratt SI, Brunette MF, Ferron JC, Santos M, Sargent J, Xie H. E-cigarette provision to promote switching in cigarette smokers with serious mental illness - a randomized trial. Nicotine & Tobacco Research 2022;6(24):1405-12. [DOI: doi: 10.1093/ntr/ntac082] - PMC - PubMed
Price 2022 {published data only}
    1. Price AD, Coffey M, Houston L, Cook PA. Evaluation of a pharmacy supported e-cigarette smoking cessation intervention in Northwest England. BMC Public Health 2022;22:1326. [DOI: 10.1186/s12889-022-13711-x] - DOI - PMC - PubMed
Pulvers 2018 {published data only}
    1. Pulvers K, Emami AS, Nollen NL, Romero DR, Strong DR, Benowitz NL, et al. Tobacco consumption and toxicant exposure of cigarette smokers using electronic cigarettes. Nicotine & Tobacco Research 2018;20(2):206-14. - PMC - PubMed
Pulvers 2020 {published and unpublished data}
    1. Arnold M, Nollen N, Mayo M, Ahluwalia J, Leavens E, Zhang G et al. Dual use of cigarettes and e-cigarettes in African American and LatinX smokers: Secondary analyses from a randomised controlled e-cigarettes switching trial. In: Society for Research on Nicotine and Tobacco (SRNT) 2021 Annual Meeting. February 24-27 2021 virtual:POD4-2 p31. - PMC - PubMed
    1. Arnold MJ, Nollen NL, Mayo MS, Ahluwalia JS, Leavens EL, Zhang G, Rice M, et al. Harm reduction associated with dual use of cigarettes and e-cigarettes in Black and Latino smokers: secondary analyses from a randomized controlled e-cigarette switching trial. Nicotine & Tobacco Research 2021;23(11 2021 Oct 7;23(11):192-1876. [DOI: 10.1093/ntr/ntab069] - DOI - PMC - PubMed
    1. Leavens ELS, Nollen N, Ahluwalia J, Mayo M, Rice M, Brett E, et al. Changes in dependence, withdrawal, and craving among adult smokers who switch to nicotine salt pod-based e-cigarettes. In: Society for Research on Nicotine and Tobacco (SRNT) 2021 Annual Meeting. February 24-27 2021 virtual:POD53-1 p96, C-6 p116. - PMC - PubMed
    1. Leavens ELS, Nollen N, Ahluwalia JS, Mayo MS, Rice M, Brett EI et al. Changes in dependence, withdrawal, and craving among adult smokers who switch to nicotine salt pod-based e-cigarettes. Addiction 2021;117(1):207-215. [DOI: 10.1111/add.15597] - DOI - PMC - PubMed
    1. Lee SC, Maglalang DD, Avila JC, Leavens ELS, Nollen NL Pulvers K, et al. Change in e-cigarette risk perception and smoking behavior of Black and Latinx individuals who smoke. Drug and Alcohol Dependence 2023;245:109824. [DOI: 10.1016/j.drugalcdep.2023.109824] - DOI - PMC - PubMed
Russell 2021 {published and unpublished data}
    1. Russell C, McKeganey N, Katsampouris E, Satchwell A, Haseen F. A randomised community-based trial of a closed-system pod e-vapour product and nicotine replacement therapy for cigarette abstinence and reduction. Society for Research on Nicotine and Tobacco (SRNT) 2021 Annual Meeting February 24-27 2021 virtual:PH-353 p230.
Scheibein 2020 {published and unpublished data}
    1. Scheibein F, McGirr K, Morrison A, Roche, Wells JS. An exploratory non-randomized study of a 3-month electronic nicotine delivery system (ENDS) intervention with people accessing a homeless supported temporary accommodation service (STA) in Ireland. Harm Reduction Journal 2020;17(1):73. - PMC - PubMed
Skelton 2022 {published data only}
    1. ACTRN12617000905369. Smoking reduction interventions for smoking cessation. ncbi.nlm.nih.gov/pmc/articles/PMC6953262/ (first received 9 June 2017). [DOI: 10.1002/14651858.CD013183.pub2] - DOI
    1. Lum A, Skelton E, Robinson M, Guillaumier A, Wynne O, Gartner C, et al. Barriers and facilitators to using vaporised nicotine products as smoking cessation aids among people receiving treatment for substance use disorder. Addictive Behaviors 2021;124:107097. [DOI: 10.1016/j.addbeh.2021.107097] - DOI - PubMed
    1. Skelton E, Lum A, Robinson M, Dunlop A, Guillaumier A, Baker A, et al. A pilot randomised controlled trial of abrupt versus gradual smoking cessation in combination with vaporised nicotine products for people receiving alcohol and other drug treatment. Addictive Behaviors 2022;131:107328. [DOI: doi: 10.1016/j.addbeh.2022.107328] - PubMed
Smith 2020 {published and unpublished data}
    1. Smith TT, Heckman BW, Wahlquist AE, Cummings KM, Carpenter MJ. The impact of e-liquid propylene glycol and vegetable glycerin ratio on ratings of subjective effects, reinforcement value, and use in current smokers. Nicotine & Tobacco Research 2020;22(5):791-7. - PMC - PubMed
Stein 2016 {published data only}
    1. Stein MD, Caviness C, Grimone K, Audet D, Anderson BJ, Bailey GL. An open trial of electronic cigarettes for smoking cessation among methadone-maintained smokers. Nicotine & Tobacco Research 2016;18(5):1157-62. - PMC - PubMed
Strasser 2016 {published data only}
    1. Strasser AA, Souprountchouk V, Kaufmann A, Blazekovic S, Leone F, Benowitz NL, et al. Nicotine replacement, topography, and smoking phenotypes of e-cigarettes. Tobacco Regulatory Science 2016;2(4):352-62. - PMC - PubMed
Tattan‐Birch 2023 {published data only}
    1. ISRCTN16931827. A trial to assess the benefit of offering an e-cigarette starter kit to smokers attempting to stop smoking with varenicline. isrctn.com/ISRCTN16931827 (first received 23 August 2018).
    1. Tattan-Birch H, Kock L, Brown J, Beard E, Bauld L, West R, et al. E-cigarettes to augment stop smoking in-person support and treatment with varenicline (E-ASSIST): a pragmatic randomised controlled trial. Nicotine & Tobacco Research 2023;25(3):395-403. [DOI: 10.1093/ntr/ntac149] - DOI - PMC - PubMed
Tseng 2016 {published data only}
    1. Guttentag A, Tuo-Yen T, Shelley D, Thomas K. Analyzing trajectories of acute cigarette reduction post-introduction of an e-cigarette using ecological momentary assessment data. International Journal of Environmental Research and Public Health 2022;19(12):7452. [DOI: 10.3390/ijerph19127452] - DOI - PMC - PubMed
    1. Guttentag A. Do e-cigarettes "Work" for smokers as a step on the way to cessation? An analysis of the temporal and spatial correlates of switching in a harm reduction trial among adult smokers. Dissertation Abstracts International: Section B: The Sciences and Engineering 2021;82:8-B.
    1. NCT02628964. Assessing the use of electronic cigarettes (e-cigarettes) as a harm reduction strategy. clinicaltrials.gov/show/NCT02628964 (accessed 17 February 2016).
    1. Tseng TY, Ostroff JS, Campo A, Gerard M, Kirchner T, Rotrosen J, et al. A randomized trial comparing the effect of nicotine versus placebo electronic cigarettes on smoking reduction among young adult smokers. Nicotine & Tobacco Research 2016;18(10):1937-43. - PMC - PubMed
Valentine 2018 {published data only}
    1. Valentine GW, Hefner K, Jatlow PI, Rosenheck RA, Gueorguieva R, Sofuoglu M. Impact of e-cigarettes on smoking and related outcomes in veteran smokers with psychiatric comorbidity. Journal of Dual Diagnosis 2018;14(1):2-13. - PMC - PubMed
Van Staden 2013 {published data only}
    1. Van Staden SR, Groenewald M, Engelbrecht R, Becker PJ, Hazelhurst LT. Carboxyhaemoglobin levels, health and lifestyle perceptions in smokers converting from tobacco cigarettes to electronic cigarettes. South African Medical Journal 2013;103(11):865-8. - PubMed
Vickerman 2022 {published data only}
    1. NCT03575468. Enhanced e-cigarette coaching intervention for dual users of cigarettes and e-cigarettes. clinicaltrials.gov/ct2/show/NCT03575468 (first received 2 July 2018).
    1. Vickerman KA, Carpenter KM, Miles LN, Hsu JM, Watt KA, Brandon TH, et al. A randomized pilot of a tailored smoking cessation quitline intervention for individuals who smoke and vape. Nicotine & Tobacco Research 2022;24(11):1811-20. [DOI: ] - PMC - PubMed
    1. Vickerman KA, Carpenter KM, Watt K, Miles L, Hsu J, Brandon T, et al. A behavioral smoking cessation intervention for Quitline callers who also use e-cigarettes. In: Society for Research on Nicotine and Tobacco (SRNT) 2021 Annual Meeting; February 24-27 2021 (virtual). 2021:POD14-1 p50.
Wadia 2016 {published data only}
    1. Wadia R, Booth V, Yap HF, Moyes DL. A pilot study of the gingival response when smokers switch from smoking to vaping. British Dental Journal 2016;221(11):722-6. - PubMed
Wagener 2023 {published data only}
    1. Wagener T, Beebe L, Businelle M, Carpenter M, Hinton A, Hart J, et al. E-cigarette versus combination nicotine replacement therapy delivered through state quitlines on smoking abstinence following a recent failed quit attempt: a randomized trial. In: Society for Research on Nicotine and Tobacco (SRNT) 29th Annual Meeting; 2023 Mar 1-4; San Antonio (TX), USA. SYM5-2. 2023.
Walele 2018 {published data only}
    1. Cravo AS, Bush J, Sharma G, Savioz R, Martin C, Craige S, et al. A randomised, parallel group study to evaluate the safety profile of an electronic vapour product over 12 weeks. Regulatory Toxicology and Pharmacology 2016;81:S1-S14. - PubMed
    1. NCT02029196. A randomised, parallel group, multi-centre study to evaluate the safety profile of the ITG EVP G1 product. clinicaltrials.gov/show/NCT02029196 (accessed 16 July 2014).
    1. NCT02143310. A multi-centre study to evaluate the safety of use of electronic vapour products for two years. clinicaltrials.gov/show/NCT02143310 (accessed 16 July 2014).
    1. Walele T, Bush J, Koch A, Savioz R, Martin C, O'Connell G. Evaluation of the safety profile of an electronic vapour product used for two years by smokers in a real-life setting. Regulatory Toxicology and Pharmacology 2018;92:226-38. - PubMed
Walker 2020 {published data only}
    1. NCT02521662. A randomised-controlled clinical trial to evaluate the effectiveness and safety of combining nicotine patches with e-cigarettes (with and without nicotine) plus behavioural support, on smoking abstinence. clinicaltrials.gov/show/NCT02521662 (accessed 17 February 2016).
    1. Walker N, Parag V, Verbiest M, Laking G, Laugesen M, Bullen C. Nicotine patches used in combination with e-cigarettes (with and without nicotine) for smoking cessation: a pragmatic, randomised trial. Lancet. Respiratory Medicine 2020;8(1):54-64. - PubMed
    1. Walker N, Verbiest M, Kurdziel T, Laking G, Laugesen M, Parag V, et al. Effectiveness and safety of nicotine patches combined with e-cigarettes (with and without nicotine) for smoking cessation: study protocol for a randomised controlled trial. BMJ Open 2019;9(2):e023659. - PMC - PubMed
White 2021 {published and unpublished data}
    1. NCT03185546. Project 2 cigarette and e-cigarette nicotine content and e-liquid flavors. clinicaltrials.gov/ct2/show/NCT03185546 (first received May 14 2021).
    1. White CM, Denlinger-Apte RL, Tessier KM, Koopmeiners JS, Hatsukami DK, Strasser AA. Cigarette nicotine reduction in the presence of an alternative: investigating how cigarette nicotine content and e-liquid content affect smoking. In: Society for Research on Nicotine and Tobacco (SRNT) 2021 Annual Meeting February 24-27 2021 (virtual). 2021:SYM2C p2-3.
    1. White CM, Tessier KM, Koopmeiners JS, Denlinger-Apte RL, Cobb CO, Lane T, et al. Preliminary evidence on cigarette nicotine reduction with concurrent access to an e-cigarette: manipulating cigarette nicotine content, e-liquid nicotine content, and e-liquid flavor availability. Preventive Medicine 2022;Dec; 165(Pt B):107213:Epub. [DOI: ] - PMC - PubMed
Yingst 2020 {published data only}
    1. Yingst J, Foulds J, Zurlo J, Steinberg MB, Eissenberg T, Du P. Acceptability of electronic nicotine delivery systems (ENDS) among HIV positive smokers. AIDS Care 2020;32(10):1224-8. - PMC - PubMed

References to studies excluded from this review

Adkison 2013 {published data only}
    1. Adkison SE, O'Connor RJ, Bansal-Travers M, Hyland A, Borland R, Yong HH, et al. Electronic nicotine delivery systems: international tobacco control four-country survey. American Journal of Preventive Medicine 2013;44(3):207-15. - PMC - PubMed
Al‐Delaimy 2015 {published data only}
    1. Al-Delaimy WK, Myers MG, Leas EC, Strong DR, Hofstetter CR. E-cigarette use in the past and quitting behavior in the future: a population-based study. American Journal of Public Health 2015;105(6):1213-9. - PMC - PubMed
    1. Donzelli A. E-cigarettes may impair ability to quit, but other explanations are possible. American Journal of Public Health 2015;105(11):e1. - PMC - PubMed
Bianco 2019 {published data only}
    1. Bianco CL, Pratt SI, Ferron JC, Brunette MF. Electronic cigarette use during a randomized trial of interventions for smoking cessation among Medicaid beneficiaries with mental illness. Journal of Dual Diagnosis 2019;15(3):184-91. - PubMed
Caponnetto 2019 {published data only}
    1. Caponnetto P, Maglia M, Polosa R. Efficacy of smoking cessation with varenicline plus counselling for e-cigarettes users (VAREVAPE): a protocol for a randomized controlled trial. Contemporary Clinical Trials Communications 2019;15:100412. - PMC - PubMed
Chaumont 2019 {published data only}
    1. Chaumont M, El Channan M, Bernard A, Lesage A, Deprez G, Van Muylem A, et al. Short-term high wattage e-cigarette cessation improves cardiorespiratory outcomes in regular users: a randomized crossover trial. Journal of Hypertension 2019;Conference: 29th European Meeting on Hypertension and Cardiovascular Protection, ESH 2019. Italy. 37(Supplement 1):e8-9.
ChiCTR2100044062 {published data only}
    1. ChiCTR2100044062. Study on the kinetics of nicotine metabolism of cigarettes/e-cigarettes in Chinese healthy subjects and the effect of complete/partial replacement of cigarettes with e-cigarettes on human biomarkers, tolerance and satisfaction survey of e-cigaret [传统卷烟/电子烟在中国健康受试者中尼古丁代谢动力学研究及用电子烟完全/部分替代香烟后对人体生物标志物的影响、对电子烟的耐受性及满意度调查]. Chinese Clinical Trial Registry 2021.
Collins 2019 {published data only}
    1. Collins SE, Nelson LA, Stanton J, Mayberry N, Ubay T, Taylor EM, et al. Harm reduction treatment for smoking (HaRT-S): findings from a single-arm pilot study with smokers experiencing chronic homelessness. Substance Abuse 2019;40(2):229-39. - PubMed
Cox 2019a {published data only}
    1. Cox S, Dawkins L, Doshi J, Cameron J. Effects of e-cigarettes versus nicotine replacement therapy on short-term smoking abstinence when delivered at a community pharmacy. Addictive Behaviors Reports 2019;10:100202. - PMC - PubMed
Douptcheva 2013 {published data only}
    1. Douptcheva N, Gmel G, Studer J, Deline S, Etter JF. Use of electronic cigarettes among young Swiss men. Journal of Epidemiology & Community Health 2013;67(12):1075-6. - PubMed
Dyer 2023 {published data only}
    1. Dyer ML, Khouja JN, Jackson AR, Havill MA, Dockrell MJ, Munafo MR et al. Effects of electronic cigarette e-liquid flavouring on cigarette craving. Tobacco Control 2023;e1:e3-e9. [DOI: 10.1136/tobaccocontrol-2021-056769] - DOI - PMC - PubMed
Farsalinos 2013a {published data only}
    1. Farsalinos KE, Romagna G, Tsiapras D, Kyrzopoulos S, Voudris V. Evaluating nicotine levels selection and patterns of electronic cigarette use in a group of "vapers" who had achieved complete substitution of smoking. Substance Abuse: Research and Treatment 2013;7:139-46. - PMC - PubMed
Grana 2014b {published data only}
    1. Grana RA, Popova L, Ling PM. A longitudinal analysis of electronic cigarette use and smoking cessation. JAMA Internal Medicine 2014;174(5):812-3. - PMC - PubMed
ISRCTN54776958 {published data only}
    1. ISRCTN 54776958. E-cigarette support for smoking cessation: identifying the effectiveness of intervention components in an online randomised optimisation experiment. ISRCTN. - PMC - PubMed
James 2016 {published data only}
    1. James SA, Meier EM, Wagener TL, Smith KM, Neas BR, Beebe LA. E-Cigarettes for immediate smoking substitution in women diagnosed with cervical dysplasia and associated disorders. International Journal of Environmental Health Research 2016;13(3):E288. [DOI: 10.3390/ijerph13030288] - DOI - PMC - PubMed
    1. NCT01989923. Smoking Cessation in Women With Gynecological Conditions. https://clinicaltrials.gov/ct2/show/NCT01989923 (Accessed 9 September 2022).
Kasza 2013 {published data only}
    1. Kasza KA, Bansal-Travers M, O'Connor RJ, Compton WM, Kettermann A, Borek N, et al. Cigarette smokers' use of unconventional tobacco products and associations with quitting activity: findings from the ITC-4 U.S. cohort. Nicotine & Tobacco Research 2013;16(6):672-81. - PMC - PubMed
Kotlyar 2022 {published data only}
    1. Kotlyar M, Shanley R, Dufresne SR, Corcoran GA, Hatsukami DK. Effect on tobacco use and subjective measures of including e-cigarettes in a simulated ban of menthol in combustible cigarettes. Nicotine & Tobacco Research 2022;24(9):1448-57. [DOI: DOI: 10.1093/ntr/ntac107] - PMC - PubMed
Manzoli 2015 {published data only}
    1. Manzoli L, Flacco ME, Fiore M, La Vecchia C, Marzuillo C, Gualano MR, et al. Electronic cigarettes efficacy and safety at 12 months: cohort study. PLOS One 2015;10(6):e0129443. - PMC - PubMed
    1. Manzoli L, La Vecchia C, Flacco ME, Capasso L, Simonetti V, Boccia S, et al. Multicentric cohort study on the long-term efficacy and safety of electronic cigarettes: study design and methodology. BMC Public Health 2013;13(1):883. - PMC - PubMed
    1. NCT01785537. The efficacy and safety of electronic cigarettes: a 5-year follow-up study. clinicaltrials.gov/ct2/show/NCT01785537 (first received 7 February 2013).
Miura 2015 {published data only}
    1. Miura N, Yuki D, Minami N, Kakehi A, Futama Y. A study to investigate changes in the levels of biomarkers of exposure to selected cigarette smoke constituents in Japanese adult male smokers who switched to a non-combustion inhaler type of tobacco product. Regulatory Toxicology and Pharmacology 2015;71(3):498-506. - PubMed
NCT03575468 {published data only}
    1. NCT03575468. Enhanced E-cigarette Coaching Intervention for Dual Users of Cigarettes and E-cigarettes. https://clinicaltrials.gov/ct2/show/NCT03575468 (first received 2 July 2018).
NCT05658471 {published data only}
    1. NCT05658471. Pharmacokinetics and Pharmacodynamics of Nicotine With Use of Standardized Research Electronic Cigarette (SREC). Clinicaltrials.gov 2022;(first received 24 August 2023). [https://classic.clinicaltrials.gov/ct2/show/NCT05658471]
Nolan 2016 {published data only}
    1. Nolan M, Leischow S, Croghan I, Kadimpati S, Hanson A, Schroeder D, et al. Feasibility of electronic nicotine delivery systems in surgical patients. Nicotine & Tobacco Research 2016;18(8):1757-62. - PMC - PubMed
Palamidas 2014 {published data only}
    1. Palamidas A, Gennimata SA, Kaltsakas G, Tsikrika S, Vakali S, Gratziou C, et al. Acute effect of an e-cigarette with and without nicotine on lung function. Tobacco Induced Diseases 2014;12(Suppl 1):A34.
Pearson 2012 {published data only}
    1. Pearson JL, Richardson A, Niaura RS, Vallone DM, Abrams DB. E-cigarette awareness, use, and harm perceptions in US adults. American Journal of Public Health 2012;102(9):1758-66. - PMC - PubMed
Song 2020 {published data only}
    1. NCT02596685. Effects of Electronic Cigarette Use on the Lungs. https://www.clinicaltrials.gov/ct2/show/NCT02596685 (Accessed 8 September 2022).
    1. Song M-A, Reisinger SA, Freudenheim JL, Brasky TM, Mathe EA, McElroy JP, et al. Effects of electronic cigarette constituents on the human lung: a pilot clinical trial. Cancer Prevention Research 2020;13(2):145-52. - PMC - PubMed
St.Helen 2020 {published data only}
    1. StHelen G, Nardone N, Addo N, Dempsey D, Havel C, Jacob P, et al. Differences in nicotine intake and effects from electronic and combustible cigarettes among dual users. Addiction 2020;115(4):757-67. - PMC - PubMed
Tucker 2018 {published data only}
    1. Tucker MR, Laugesen M, Bullen C, Grace RC. Predicting short-term uptake of electronic cigarettes: effects of nicotine, subjective effects, and simulated demand. Nicotine & Tobacco Research 2018;20(10):1265-71. - PubMed
Wagener 2014 {published data only}
    1. Wagener TL, Meier E, Hale JJ, Oliver ER, Warner ML, Driskill LM, et al. Pilot investigation of changes in readiness and confidence to quit smoking after e-cigarette experimentation and 1 week of use. Nicotine & Tobacco Research 2014;16(1):108-14. - PubMed
Walele 2016a {published data only}
    1. Walele T, Sharma G, Savioz R, Martin C, Williams J. A randomised, crossover study on an electronic vapour product, a nicotine inhalator and a conventional cigarette. Part A: Pharmacokinetics. Regulatory Toxicity 2016;74:187-92. - PubMed
Walele 2016b {published data only}
    1. Walele T, Sharma G, Savioz R, Martin C, Williams J. A randomised, crossover study on an electronic vapour product, a nicotine inhalator and a conventional cigarette. Part B: Safety and subjective effects. Regulatory Toxicity 2016;74:193-9. - PubMed

References to ongoing studies

ACTRN12619001787178 {published data only}
    1. ACTRN12619001787178. Project NEAT: nicotinE as treatment for tobacco smoking following discharge from residential withdrawal services. www.who.int/trialsearch/Trial2.aspx?TrialID=ACTRN12619001787178 (first received 18 November 2019).
    1. Bonevski B, Trigg J, Rich J, Williams E, Baker AL, Walker N, et al. Perceptions of nicotine products for tobacco smoking cessation following discharge from alcohol and other drug residential withdrawal services: a qualitative analysis. In: SRNT (Society for Research on Nicotine and Tobacco) 29th Annual Meeting 2023 Mar 1-4; San Antonio (TX), USA. SYM13-2. 2023:p 17.
ACTRN12621000148875 {published data only}
    1. ACTRN12621000148875. HARMONY: harm reduction for opiates, nicotine and you. www.who.int/trialsearch/Trial2.aspx?TrialID=ACTRN12621000148875 (first received February 12 2021). [CENTRAL: www.cochranelibrary.com/central/doi/10.1002/central/CN-02240640/full]
Berlin 2019 {published data only}
    1. Berlin I, Dautzenberg B, Lehmann B, Palmyre J, Liégey E, De Rycke Y, et al. Randomised, placebo-controlled, double-blind, double-dummy, multicentre trial comparing electronic cigarettes with nicotine to varenicline and to electronic cigarettes without nicotine: the ECSMOKE trial protocol. BMJ Open 2019;9(5):e028832. - PMC - PubMed
    1. NCT03630614. Randomized trial of electronic cigarettes with or without nicotine in smoking cessation (ECSMOKE). clinicaltrials.gov/ct2/show/NCT03630614 (first received 15 August 2018).
Caponnetto 2014 {published data only}
    1. Caponnetto P, Polosa R, Auditore R, Minutolo G, Signorelli M, Maglia M, et al. Smoking cessation and reduction in schizophrenia (SCARIS) with e-cigarette: study protocol for a randomized control trial. Trials [electronic resource] 2014;15:88. - PMC - PubMed
    1. NCT01979796. Antismoking effects of electronic cigarettes in subjects with schizophrenia and their potential influence on cognitive functioning: design of a randomized trial. Smoking Cessation And Reduction In Schizophrenia (The SCARIS Study). clinicaltrials.gov/show/NCT01979796 (accessed 16 July 2014).
Cox 2022 {published data only}
    1. Cox S, Bauld L, Brown R, Carlise M, Ford A, Hajek P. Evaluating the effectiveness of e-cigarettes compared with usual care for smoking cessation when offered to smokers at homeless centres: protocol for a multi-centre cluster-randomized controlled trial in Great Britain. Addiction 2022;117(7):2096-2107. [DOI: ] - PMC - PubMed
    1. ISRCTN18566874. E-cigarettes vs usual care for smoking cessation when offered at homeless centres. isrctn.com/ISRCTN18566874 (Accessed 8 September 2022) (first received October 12 2021). [DOI: ]
El‐Khoury  2021 {published data only}
    1. El-Khoury F, El Aarbaoui T, Heron M, Hejblum G, Metadieu B, Le Faou AL, et al. Smoking cessation using preference-based tools among socially disadvantaged smokers: study protocol for a pragmatic, multicentre randomised controlled trial. BMJ Open 2021;11(6):e048859. [DOI: 10.1136/bmjopen-2021-048859] - DOI - PMC - PubMed
    1. Heron M, Le Faou AL, Ibanez G, Metadieu B, Melchior M, El-Khoury L, et al. Smoking cessation using preference-based tools: a mixed method pilot study of a novel intervention among smokers with low socioeconomic position.. Addiction Science & Clinical Practice 2021;16(1):43. [DOI: ] - PMC - PubMed
    1. NCT04654585. Preference-based tools for smoking cessation among disadvantaged smokers, a pragmatic randomised controlled trial [Sevrage tabagique à l'aide des outils dédiés selon la préférence, un essai randomisé contrôlé pragmatique]. clinicaltrials.gov/ct2/show/NCT04654585 (first received December 4 2020).
Holliday 2022 {published data only}
    1. Holliday R, Preshaw P, McColl E, Ryan V, Cherlin S, Wilson N, et al. Research protocol for the ENHANCE-D trial: enhancing dental health advice. Journal of Clinical Periodontology 2022;49(Supp 23):79. [DOI: 10.1111/jcpe.13634] - DOI
Howard 2022 {published data only}
    1. ACTRN12621000076875. Vaporised nicotine products versus nicotine replacement therapy for tobacco smoking cessation among low-socioeconomic status smokers: a randomised controlled trial. trialsearch.who.int/Trial2.aspx?TrialID=ACTRN12621000076875 (first received January 29 2021). [CENTRAL: www.cochranelibrary.com/es/central/doi/10.1002/central/CN-02240824/full]
    1. Howard BC, McRobbie H, Petrie D, Barker D, Mendelsohn C, Anderson J, et al. Effectiveness, safety and cost-effectiveness of vaporized nicotine products versus nicotine replacement therapy for tobacco smoking cessation in a low-socioeconomic status Australian population: a study protocol for a randomized controlled trial. Trials 2022;23(1):777. [DOI: ] - PMC - PubMed
ISRCTN13158982 {published data only}
    1. ISRCTN13158982. Enhancing dental health advice. isrctn.com/ISRCTN13158982 (first received May 10 2022). [DOI: ]
ISRCTN17691451 {published data only}
    1. ISRCTN17691451. ESCAPE: E-cigarettes for smoking cessation and reduction in people with mental illness [E-cigarettes for smoking cessation and reduction in people with mental illness - a randomised pilot feasibility trial]. isrctn.com/ISRCTN17691451 (first received September 30 2021). [DOI: ]
ISRCTN61193406 {published data only}
    1. ISRCTN61193406. Do e-cigarettes help smokers quit when not accompanied by intensive behavioural support? who.int/trialsearch/Trial2.aspx?TrialID=ISRCTN61193406 2020 (first received 11 August 2020).
Krysinski 2021 {published data only}
    1. Krysinski A, Russo C, John S, Belsey JD, Campagna D, Caponnetto P, et al. International randomised controlled trial evaluating metabolic syndrome in type 2 diabetic cigarette smokers following switching to combustion-free nicotine delivery systems: the DIASMOKE protocol. BMJ Open 2021;11(4):e045396. [DOI: 10.1136/bmjopen-2020-045396] - DOI - PMC - PubMed
    1. NCT04231838. Metabolic syndrome in diabetic smokers using cigarettes & combustion-free nicotine delivery systems (DIASMOKE). clinicaltrials.gov/ct2/show/NCT04231838 (first received January 18 2020).
Murray 2020 {published data only}
    1. ISRCTN63825779. Yorkshire Enhanced Stop Smoking (YESS). isrctn.com 2018.
    1. Murray RL, Brain K, Britton J, Quinn-Scoggins HD, Lewis S, McCutchan GM, et al. Yorkshire Enhanced Stop Smoking (YESS) study: a protocol for a randomised controlled trial to evaluate the effect of adding a personalised smoking cessation intervention to a lung cancer screening programme. BMJ Open 2020;10(9):e037086. - PMC - PubMed
    1. NCT03750110. Yorkshire Enhanced Stop Smoking Study (YESS). clinicaltrials.gov 2017.
NCT01842828 {published data only}
    1. NCT01842828. E-cigarettes as an addition to multi-component treatment for tobacco dependence: a pilot study. clinicaltrials.gov/show/NCT01842828 (first received 16 July 2014).
NCT01989923 {published data only}
    1. NCT01989923. Immediate smoking cessation for patients at risk for cervical dysplasia, cervical cancer and lower genital tract dysplasia and cancer - a feasibility study comparing nicotine replacement therapy with the electronic nicotine delivery system. clinicaltrials.gov/show/NCT01989923 (first received November 21 2013).
NCT02124187 {published data only}
    1. NCT02124187. Smoking cessation and reduction in depression (SCARID). clinicaltrials.gov/show/NCT02124187 (first received April 28 2014).
NCT02398487 {published data only}
    1. NCT02398487. Personal Vaporizer vs Cigalike (VAPECIG 2) [Head-to-head comparison of personal vaporizers versus cigalike: prospective 6-month randomized control design study]. clinicaltrials.gov/show/NCT02398487 (first received March 25 2015).
NCT02590393 {published data only}
    1. NCT02590393. The role of nicotine and non-nicotine alkaloids in e-cigarette use and dependence. clinicaltrials.gov/show/NCT02590393 (first received 17 February 2016).
NCT03113136 {published data only}
    1. NCT03113136. Examination of low wattage and high wattage e-cigarettes (SWITCH). clinicaltrials.gov/ct2/show/study/NCT03113136 (first received April 13 2017).
NCT03249428 {published data only}
    1. NCT03249428. E-cigarette inner city RCT [A community-based participatory action pragmatic randomized controlled trial using electronic-cigarette for tobacco dependence in the inner city population with a holistic approach]. clinicaltrials.gov/ct2/show/NCT03249428 (first received August 15 2017).
NCT03277495 {published data only}
    1. NCT03277495. Predictors and consequences of combustible cigarette smokers' switch to standardized research e-cigarettes. clinicaltrials.gov/ct2/show/NCT03277495 (first received September 11 2017).
NCT03625986 {published data only}
    1. NCT03625986. Does switching to nicotine containing electronic cigarettes reduce health risk markers. clinicaltrials.gov/ct2/show/NCT03625986 (first received August 10 2018).
NCT03700112 {published data only}
    1. NCT03700112. Clinical study comparing 7 ENDS products and 1 combustible cigarette using 2 delivery methods. clinicaltrials.gov/ct2/show/NCT03700112 (first received 7 December 2018).
NCT03962660 {published data only}
    1. NCT03962660. Harm Reduction for Tobacco Smoking with support of Tobacco-Replacing Electronic Nicotine Delivery Systems (HaRTS-TRENDS). clinicaltrials.gov/ct2/show/record/NCT03962660 (first received 24 May 2019).
NCT04003805 {published data only}
    1. NCT04003805. Biomarkers of exposure and effect in standardized research e-cigarette (SREC) users. clinicaltrials.gov/ct2/show/NCT04003805 (first received July 1 2019).
NCT04058717 {published data only}
    1. NCT04058717. Low nicotine cigarettes plus electronic cigarettes [Randomized trial of low nicotine cigarettes plus electronic cigarettes in smokers]. clinicaltrials.gov/ct2/show/NCT04058717 (first received August 15 2019).
NCT04063267 {published data only}
    1. NCT04063267. Electronic cigarettes as a harm reduction strategy in individuals with substance use disorder. clinicaltrials.gov/ct2/show/NCT04063267 (first received 21 August 2019).
NCT04090879 {published data only}
    1. DeAtley T, Harrison A, Camacho B, Cassidy R, Kuo C, Higgins ST, et al. Subjective experiences, contexts, and risk perceptions of very low content cigarettes and electronic cigarettes among people with affective disorders who smoke. In: Society for Research on Nicotine and Tobacco Annual Meeting, 2022 March; Baltimore USA. 2022.
    1. DeAtley T, Harrison A, Cassidy R, Kuo C, Higgins ST, Tidey JW. Subjective experiences, contexts, and risk perceptions of very low nicotine content cigarettes and electronic cigarettes among people with depression and anxiety disorders who smoke. Drug and Alcohol Dependence 2023;244:109767. - PMC - PubMed
    1. NCT04090879. Low nicotine content cigarettes in vulnerable populations: affective disorders. clinicaltrials.gov/ct2/show/NCT04090879 (first received September 16 2019).
NCT04092101 {published data only}
    1. NCT04092101. Low nicotine content cigarettes in vulnerable populations: opioid use disorder. clinicaltrials.gov/ct2/show/NCT04092101 (first received September 17 2019).
NCT04092387 {published data only}
    1. NCT04092387. Low nicotine content cigarettes in vulnerable populations: women of reproductive age. clinicaltrials.gov/ct2/show/NCT04092387 (first received September 17 2019).
NCT04218708 {published data only}
    1. NCT04218708. Electronic cigarettes as a harm reduction strategy among people living with HIV/AIDS. clinicaltrials.gov/ct2/show/NCT04218708 (first received January 6 2020).
NCT04238832 {published data only}
    1. NCT04238832. Salt-based e-cigarette and IQOS Study. clinicaltrials.gov/show/NCT04238832 (first received 18 January 2020).
NCT04452175 {published data only}
    1. NCT04452175. Cigarette consumption after switchinG to high or low nicotine strENght E-cigaretteS In Smokers With Schizophrenia (GENESIS). clinicaltrials.gov/show/NCT04452175 (first received 30 June 2020).
NCT04465318 {published data only}
    1. NCT04465318. Electronic cigarettes as a harm reduction strategy among patients with COPD. clinicaltrials.gov/ct2/show/NCT04465318 (first received July 10 2020).
    1. Stevens ER, Lei L, Cleland CM, Berger KM, Sherman SE, Vojjala M. Electronic cigarettes as a harm reduction strategy among patients with COPD: protocol for an open-label two arm randomized controlled pilot trial. Addiction Science & Clinical Practice 2022;17(1):2. [DOI: 10.1186/s13722-021-00284-0] - DOI - PMC - PubMed
    1. Vojjala M, Wilker OG, Nicholson A, Morgan T, Rozon I, Stevens ER et al. Electronic cigarettes and counseling as a harm reduction strategy among patients with COPD, asthma, CAD/PAD. In: SRNT 29th Annual Meeting; 2023 Mar 1-4; San Antonio (TX), USA POS4-100. 2023:206.
NCT04521647 {published data only}
    1. NCT04521647. Effects of menthol in e-cigarettes on smoking behaviors. clinicaltrials.gov/ct2/show/NCT04521647 (first received August 20 2020).
NCT04649645 {published data only}
    1. NCT04649645. International randomized controlled trial evaluating changes in oral health in smokers after switching to combustion-free nicotine delivery systems. clinicaltrials.gov/show/NCT04649645 (first received 02 December 2020).
NCT04708106 {published data only}
    1. NCT04708106. Characterization of product use in smokers switching from cigarettes to a RELX electronic nicotine delivery system. clinicaltrials.gov/ct2/show/NCT04708106 (first posted 13 January 2021).
NCT04709471 {published data only}
    1. NCT04709471. E-cigarette nicotine study. clinicaltrials.gov/ct2/show/NCT04709471 (first posted 14 January 2021).
NCT04725656 {published data only}
    1. NCT04725656. Concentration Impact Nicotine Salt (CINS). clinicaltrials.gov/ct2/show/NCT04725656 (first posted January 27 2021).
NCT04946825 {published data only}
    1. NCT04946825. Quit smoking study for people who use e-cigarettes [ A randomized controlled trial of smoking cessation treatment for young adult dual users of combustible and electronic cigarettes]. clinicaltrials.gov/ct2/show/NCT04946825 (first received July 1 2021).
NCT05023096 {published data only}
    1. NCT05023096. Potential effects of electronic nicotine delivery system flavor regulations on African American menthol smokers (RVA flavors) [Effects of electronic nicotine delivery system flavor regulations on tobacco behavior, toxicity, and abuse liability among African American menthol smokers]. clinicaltrials.gov/ct2/show/NCT05023096 (first received August 26 2021).
NCT05144542 {published data only}
    1. NCT05144542. Risk and benefits of electronic cigarettes to older smokers at high risk for lung cancer. www.clinicaltrials.gov/ct2/show/NCT05144542 (first received December 3 2021).
NCT05199480 {published data only}
    1. NCT05199480. Understanding the impact of cartridge-based electronic cigarettes and generated aerosols on cardiopulmonary health. clinicaltrials.gov/ct2/show/NCT05199480 (first received January 20 2022).
NCT05205811 {published data only}
    1. NCT05205811. The effects of combination zonisamide and bupropion on switching to an electronic cigarette [A randomized controlled trial to determine the effects of combination zonisamide and bupropion on switching to an electronic cigarette]. clinicaltrials.gov/ct2/show/NCT05205811 (first received January 25 2022).
NCT05206435 {published data only}
    1. NCT05206435. Methadone-maintained smokers switching to e-cigarettes (SHINE). clinicaltrials.gov/ct2/show/NCT05206435 (first received January 25 2022).
NCT05257629 {published data only}
    1. NCT05257629. Aggressive smoking cessation therapy post-acute coronary syndrome (ASAP) trial. www.clinicaltrials.gov/ct2/show/NCT05257629 (first received February 25 2022).
NCT05278065 {published data only}
    1. NCT05278065. E-cigarettes for harm reduction in adult with asthma (SWAP) [Complimentary electronic cigarettes for harm reduction among adult smokers with asthma]. clinicaltrials.gov/ct2/show/NCT05278065 (first received March 14 2022).
NCT05311085 {published data only}
    1. NCT05311085. Cytisine and e-cigarettes with supportive text-messaging for smoking cessation (Cess@Tion). clinicaltrials.gov/ct2/show/NCT05311085 (first received April 5 2022).
NCT05327439 {published data only}
    1. NCT05327439. Using alternative nicotine delivery systems (ANDS) to reduce harm for low SES cigarette smokers (Tri-PEC study). clinicaltrials.gov/ct2/show/NCT05327439 (first received April 14 2022).
NCT05510154 {published data only}
    1. NCT05510154. COPD e-cigarette topography training. clinicaltrials.gov/ct2/show/NCT05510154 (first received 22 August 2022).
NCT05525078 {published and unpublished data}
    1. NCT05525078. Quit or switch: e-cigarette study. clinicaltrials.gov/ct2/show/NCT05525078 (first received 1 September 2022).
NCT05555069 {published data only}
    1. NCT05555069. The impact of menthol flavoring on switching in adult menthol smokers. clinicaltrials.gov/ct2/show/NCT05555069 (first received 26 September 2022).
NCT05610514 {published data only}
    1. NCT05610514. Pulmonary and cardiac effects of e-cigarette use in pulmonary patients who smoke cigarettes. clinicaltrials.gov/ct2/show/NCT05610514 (first received 9 November 2022).
NCT05703672 {published data only}
    1. NCT05703672. Switching to e-cigarettes in African-American smokers. clinicaltrials.gov/ct2/show/NCT05703672 (first received 30 January 2023).
NCT05815199 {published data only}
    1. NCT05815199. E-cigarettes for harm reduction among smokers with serious mental illness. clinicaltrials.gov/study/NCT05815199 (first received 4 April 2023).
NCT05825924 {published data only}
    1. NCT05825924. Effectiveness of different THR products in adult population. clinicaltrials.gov/ct2/show/NCT05825924 (first received 24 April 2023).
NCT05881304 {published data only}
    1. NCT05881304. Switching individuals in treatment for opioid use disorder who smoke cigarettes to the SREC (SWITCHED). clinicaltrials.gov/ct2/show/NCT05881304 (first received 31 May 2023).
NCT05887947 {published data only}
    1. NCT05887947. Impact of e-cigarette nicotine concentration on compensation. clinicaltrials.gov/ct2/show/NCT05887947 (first received 5 June 2023).
Notley 2023 {published data only}
    1. NCT04854616. Cessation of Smoking Trial in the Emergency Department (CoSTED). clinicaltrials.gov/ct2/show/NCT04854616 (date first received April 22 2021).
    1. Notley C, Clark L, Belderson P, Ward E, Clark AB, Parrott S, et al. Cessation of smoking trial in the emergency department (CoSTED): protocol for a multicentre randomised controlled trial. BMJ Open 2023;13(1):e064585. - PMC - PubMed
    1. Pope I, Notley C. Cessation of smoking trial in the emergency department. In: SRNT 29th Annual Meeting; 2023 Mar 1-4; San Antonio (TX), USA, POS2-14. 2023:119-20.

Additional references

Akiyama 2021
    1. Akiyama Y, Sherwood N. Systematic review of biomarker findings from clinical studies of electronic cigarettes and heated tobacco products. Toxicology Reports 2021;8:282-94. - PMC - PubMed
Amato 2020
    1. Amato L, Cruciani F, Solimini R, Barca A, Pacifici R, Davoli M. Effects of electronic cigarettes on health: a systematic review of the available evidence. Recenti Progressi in Medicina 2020;111(1):30-43. - PubMed
ASH 2019
    1. Action on Smoking and Health. Use of electronic cigarettes (vapourisers) among adults in Great Britain. ash.org.uk/information-and-resources/fact-sheets/statistical/use-of-e-ci... (accessed 21 July 2020).
ASH 2023
    1. Action on Smoking and Health. Use of e-cigarettes (vapes) among adults in Great Britain. Use-of-e-cigarettes-among-adults-in-Great-Britain-2023.pdf (ash.org.uk) August 2023 (accessed 27 September 2023).
Balfour 2004
    1. Balfour D. The neurobiology of tobacco dependence: a preclinical perspective on the role of dopamine projections to the nucleus. Nicotine & Tobacco Research 2004;6(6):899-912. - PubMed
Banks 2022
    1. Banks E, Yazidjoglou A, Brown S, Nguyen M, Martin M, Beckwith K. Electronic Cigarettes and Health Outcomes: Systematic Review of Global Evidence. National Centre for Epidemiology and Population Health, ANU, 2022. - PMC - PubMed
Banks 2023
    1. Banks E, Yazidjoglou A, Brown S, Nguyen M, Martin M, Beckwith K et al, . Electronic cigarettes and health outcomes: umbrella and systematic review of the global evidence. The Medical journal of Australia 2023;218(6):267-75. [DOI: 10.5694/mja2.51890] - DOI - PMC - PubMed
Barbeau 2013
    1. Barbeau AM, Burda J, Siegel M. Perceived efficacy of e-cigarettes versus nicotine replacement therapy among successful e-cigarette users: a qualitative approach. Addiction: Science & Clinical Practice 2013;8(1):5. - PMC - PubMed
Barrett 2010
    1. Barrett SP. The effects of nicotine, denicotinized tobacco, and nicotine-containing tobacco on cigarette craving, withdrawal, and self-administration in male and female smokers. Behavorial Pharmacology 2010;21(2):144-52. - PubMed
Benowitz 2010
    1. Benowitz NL. Nicotine addiction. New England Journal of Medicine 2010;362(24):2295-303. - PMC - PubMed
Besaratinia 2019
    1. Besaratinia A, Tommasi S. Vaping: a growing global health concern. EClinicalMedicine 2019;17:100208. - PMC - PubMed
Bjurlin 2021
    1. Bjurlin MA, Matulewicz RS, Roberts TR, Dearing BA, Schatz D, Sherman S, et al. Carcinogen biomarkers in the urine of electronic cigarette users and implications for the development of bladder cancer: a systematic review. European Urology Oncology 2021;4(5):766-83. - PubMed
Blount 2020
    1. Blount BC, Karwowski MP, Shields PG, Morel-Espinosa M, Valentin-Blasini L, Gardner M, et al. Vitamin E acetate in bronchoalveolar-lavage fluid associated with EVALI. New England Journal of Medicine 2020;382(8):697-705. - PMC - PubMed
Brooker 2019
    1. Brooker J, Synnot A, McDonald S, Elliott J, Turner T, et al. Guidance for the production and publication of Cochrane living systematic reviews: Cochrane Reviews in living mode;December 2019. community.cochrane.org/sites/default/files/uploads/inline-files/Transfor... (accessed 30 July 2020).
Bullen 2010
    1. Bullen C, McRobbie H, Thornley S, Glover M, Lin R, Laugesen M, . Effect of an electronic nicotine delivery device (e cigarette) on desire to smoke and withdrawal, user preferences and nicotine delivery: randomised cross-over trial. Tobacco Control 2010 2010;19(2):98-103. [DOI: 10.1136/tc.2009.031567] - DOI - PubMed
Buss 2023
    1. Buss B, Kock L, Wesr R, Beard E, Kale D, Brown J. Trends in electronic cigarette use in England, Smoking in England. https://smokinginengland.info/graphs/e-cigarettes-latest-trends 2023;July:Accessed 27th September 2023.
Butler 2022
    1. Butler AR, Lindson N, Fanshawe TR, Theodoulou A, Begh R, Hajek P, et al. Longer-term use of electronic cigarettes when provided as a stop smoking aid: systematic review with meta-analyses. Preventive Medicine 2022;165(Pt B):107182. [DOI: 10.1016/j.ypmed.2022.107182] [PMID: ] - DOI - PubMed
CDC 2020
    1. Centres for Disease Control and Prevention. Outbreak of lung injury associated with the use of e-cigarette, or vaping, products. www.cdc.gov/tobacco/basic_information/e-cigarettes/severe-lung-disease.h... Feb 2020 (accessed 12 Aug 2020).
Chaimani A
    1. Chaimani A, Caldwell DM, Li T, Higgins JPT, Salanti G. Chapter 11: Undertaking network meta-analyses. in: Higgins JPT, Thomas J, Chandler J, Cumpston M, Li T, Page MJ, Welch VA (editors) ). Cochrane Handbook for Systematic Reviews of Interventions Updated August 2023;Version 6.4(Cochrane, 2023. Available from www.training.cochrane.org/handbook).
Chan 2021
    1. Chan GCK, Stepanovic D, Lim C, Sun T, Shanmuga Anandan AS, Connor JP, et al. A systematic review of randomised controlled trials and network meta-analysis of e-cigarettes for smoking cessation. Addictive Behaviours 2021;119:106912. [DOI: 10.1016/j.addbeh.2021.106912] - DOI - PubMed
Chen 2016
    1. Chen C, Zhuang YL, Zhu SH. E-cigarette design preference and smoking cessation: a U.S. population study. American Journal of Preventive Medicine 2016;51(3):356-63. [DOI: 10.1016/j.amepre.2016.02.002] - DOI - PMC - PubMed
Covidence [Computer program]
    1. Covidence. Version accessed 30 July 2020. Melbourne, Australia: Veritas Health Innovation, 2020. Available at covidence.org.
Cox 2017
    1. Cox S, Jakes S. Nicotine and e-cigarettes: rethinking addiction in the context of reduced harm. International Journal of Drug Policy 2017;44:84-5. - PubMed
Cox 2019b
    1. Cox S, Leigh NJ, Vanderbush TS, Choo E, Goniewicz ML, Dawkins L. An exploration into "do-it-yourself" (DIY) e-liquid mixing: sers' motivations, practices and product laboratory analysis. Addictive Behaviors Reports 2019;9:100151. - PMC - PubMed
Dawkins 2013b
    1. Dawkins L, Turner J, Roberts A, Soar K. 'Vaping' profiles and preferences: an online survey of electronic cigarette users. Addiction 2013;108(6):1115-25. - PubMed
Dawkins 2016
    1. Dawkins LE, Kimber CF, Doig M, Feyerabend C, Corcoran O. Self-titration by experienced e-cigarette users: blood nicotine delivery and subjective effects. Psychopharmacology (Berl) 2016;233(14-16):2933-41. [DOI: 10.1007/s00213-016-4338-2] - DOI - PubMed
Dawkins 2018
    1. Dawkins L, Cox S, Goniewicz M, McRobbie H, Kimber C, Doig M, et al. 'Real-world' compensatory behaviour with low nicotine concentration e-liquid: subjective effects and nicotine, acrolein and formaldehyde exposure. Addiction 2018;113(10):1874-82. - PMC - PubMed
Donny 2007
    1. Donny EC, Houtsmuller E, Stitzer ML. Smoking in the absence of nicotine: behavioral, subjective and physiological effects over 11 days. Addiction 2007;102(2):324-34. - PubMed
Donny 2009
    1. Donny EC, Jones M. Prolonged exposure to denicotinized cigarettes with or without transdermal nicotine. Drug and Alcohol Dependence 2009;104(1-2):23-33. - PMC - PubMed
Donny 2015
    1. Donny EC, Denlinger RL, Tidey JW, Koopmeiners JS, Benowitz NL, Vandrey RG, et al. Randomized trial of reduced-nicotine standards for cigarettes. New England Journal of Medicine 2015;373(14):1340-9. - PMC - PubMed
Du 2020
    1. Du Y, Liu B, Xu G, Rong S, Sun Y, Wu Y, et al. Association of electronic cigarette regulations with electronic cigarette use among adults in the United States. JAMA Network Open 2020;3(1):e1920255. - PMC - PubMed
E‐cigarette ontology 2021
    1. Anonymous. E-cigarette v1. www.qeios.com/read/0WX80U (accessed prior to 3 November 2022). [URL: www.qeios.com/read/0WX80U]
Eissenberg 2010
    1. Eissenberg T, . Electronic nicotine delivery devices: ineffective nicotine delivery and craving suppression after acute administration. Tobacco Control 2010;19(1):87-8. [DOI: 10.1136/tc.2009.033498] - DOI - PMC - PubMed
Etter 2011
    1. Etter JF, Bullen C. Electronic cigarette: users profile, utilization, satisfaction and perceived efficacy. Addiction 2011;106(11):2017-28. - PubMed
European Parliament 2014
    1. European Parliament and Council of the European Union. Directive 2014/40/EU of the European Parliament and of the Council of 3 April 2014 on the approximation of the laws, regulations and administrative provisions of the Member States concerning the manufacture, presentation and sale of tobacco and related products and repealing Directive 2001/37/EC. EUR-Lex - 32014L0040 - EN - EUR-Lex (europa.eu) 2014 (accessed 25th November 2014).
Farsalinos 2014
    1. Farsalinos KE, Polosa R. Safety evaluation and risk assessment of electronic cigarettes as tobacco cigarette substitutes: a systematic review. Therapeutic Advances in Drug Safety 2014;5(2):67-86. - PMC - PubMed
Goniewicz 2012
    1. Goniewicz ML, Kuma T, Gawron M, Knysak J, Kosmider L. Nicotine levels in electronic cigarettes. Nicotine & Tobacco Research 2012;15(1):158-66. - PubMed
Goniewicz 2014
    1. Goniewicz ML, Hajek P, McRobbie H. Nicotine content of electronic cigarettes, its release in vapour and its consistency across batches: regulatory implications. Addiction 2014;109(3):500-7. - PubMed
Grabovac 2021
    1. Grabovac I, Oberndorfer M, Fischer J, Wiesinger W, Haider S, Dorner TE. Effectiveness of electronic cigarettes in smoking cessation: a systematic review and meta-analysis. Nicotine & Tobacco Research 2021;23(4):625-34. [DOI: 10.1093/ntr/ntaa181] - DOI - PubMed
GRADEpro GDT [Computer program]
    1. GRADEpro GDT. Version accessed 30 July 2020. Hamilton (ON): McMaster University (developed by Evidence Prime), 2020. Available at gradepro.org.
Gugala 2022
    1. Gugala E, Okoh CM, Ghosh S, Moczygemba LR. Pulmonary health effects of electronic cigarettes: a scoping review. Health Promotion Practice 2022;23(3):388-96. - PubMed
Hajek 1999
    1. Hajek P, West R, Foulds J, Nilsson F, Burrows S, Meadow A. Randomized comparative trial of nicotine polacrilex, a transdermal patch, nasal spray, and an inhaler. Archives of Internal Medicine 1999;159(17):2033-8. - PubMed
Hajek 2014
    1. Hajek P, Etter J-F, Benowitz N, Eissenberg T, McRobbie H. Electronic cigarettes: review of use, content, safety, effects on smokers and potential for harm and benefit. Addiction 2014;109(11):1801-10. - PMC - PubMed
Hajek 2015b
    1. Hajek P, Goniewicz ML, Phillips A, Myers Smith K, West O, McRobbie H. Nicotine intake from electronic cigarettes on initial use and after 4 weeks of regular use. Nicotine & Tobacco Research 2015;17(2):175-9. - PMC - PubMed
Hajek 2017
    1. Hajek P, Przulj D, Phillips A, Anderson R, McRobbie H. Nicotine delivery to users from cigarettes and from different types of e-cigarettes. Psychopharmacology (Berl) 2017;234(5):773-9. - PMC - PubMed
Hajek 2020
    1. Hajek P, Pittaccio K, Pesola F, Myers Smith K, Phillips-Waller A, Przulj D. Nicotine delivery and users' reactions to Juul compared with cigarettes and other e-cigarette products. Addiction 2020;115(6):1141-8. - PMC - PubMed
Hall 2020
    1. Hall W, Gartner C, Bonevski B. Lessons from the public health responses to the US outbreak of vaping-related lung injury. Addiction 2020 [Epub ahead of print]. - PubMed
Hartmann‐Boyce 2018a
    1. Hartmann-Boyce J, Chepkin SC, Ye W, Bullen C, Lancaster T. Nicotine replacement therapy versus control for smoking cessation. Cochrane Database of Systematic Reviews 2018, Issue 5. Art. No: CD000146. [DOI: 10.1002/14651858.CD000146.pub5] - DOI - PMC - PubMed
Hartmann‐Boyce 2019
    1. Hartmann-Boyce J, Hong B, Livingstone-Banks J, Wheat H, Fanshawe TR. Additional behavioural support as an adjunct to pharmacotherapy for smoking cessation. Cochrane Database of Systematic Reviews 2019, Issue 6. Art. No: CD009670. [DOI: 10.1002/14651858.CD009670.pub4] - DOI - PMC - PubMed
Hartmann‐Boyce 2021b
    1. Hartmann-Boyce J, Livingstone-Banks J, Ordonez-Mena J, Fanshawe TR, Lindson N, Freeman SC, et al. Behavioural interventions for smoking cessation: an overview and network meta-analysis. Cochrane Database of Systematic Reviews 2021, Issue 1. Art. No: CD013229. [DOI: 10.1002/14651858.CD013229.pub2] - DOI - PMC - PubMed
Hartmann‐Boyce 2022a
    1. Hartmann-Boyce J, Butler AR, Theodoulou A, Onakpoya IJ, Hajek P, Bullen C, et al. Biomarkers of potential harm in people switching from smoking tobacco to exclusive e-cigarette use, dual use, or abstinence: secondary analysis of Cochrane systematic review of trials of e-cigarettes for smoking cessation. Addiction 2023;118(3):539-45. [DOI: 10.1111/add.16063] - DOI - PMC - PubMed
Hartmann‐Boyce 2022b
    1. Hartmann-Boyce J, Begh R, Lindson N, Livingstone-Banks J, Fanshawe TR, McNeill A et al. Electronic cigarettes and subsequent cigarette smoking in young people. Cochrane Database of Systematic Reviews 2022, Issue 3. Art. No: CD015170. [DOI: 10.1002/14651858.CD015170] - DOI
Hartnett 2020
    1. Hartnett KP, Kite-Powell A, Patel MT, Haag BL, Sheppard MJ, Dias TP, et al. Syndromic surveillance for e-cigarette, or vaping, product use-associated lung injury. New England Journal of Medicine 2020;382(8):766-72. - PMC - PubMed
Higgins 2003
    1. Higgins JP, Thompson SG, Deeks JJ, Altman DG. Measuring inconsistency in meta-analyses. BMJ 2003;327(7414):557-60. - PMC - PubMed
Higgins 2011
    1. Higgins JP, Green S (editors). Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0 (updated March 2011). The Cochrane Collaboration, 2011. Available from www.cochrane-handbook.org.
Higgins 2021
    1. Higgins JP, Thomas J, Chandler J, Cumpston M, Li T, Page MJ, et al (editors). Cochrane Handbook for Systematic Reviews of Interventions version 6.2 (updated February 2021). The Cochrane Collaboration, 2021. Available from www.training.cochrane.org/handbook.
Hitchman 2015
    1. Hitchman SC, Brose LS, Brown J, Robson D, McNeill A. Associations between e-cigarette type, frequency of use, and quitting smoking: findings from a longitudinal online panel survey in Great Britain. Nicotine & Tobacco Research 2015;17(10):1187-94. - PMC - PubMed
Huang 2019
    1. Huang J, Duan Z, Kwok J, Binns S, Vera LE, Kim Y, et al. Vaping versus JUULing: how the extraordinary growth and marketing of JUUL transformed the US retail e-cigarette market. Tobacco Control 2019;28(2):146-51. - PMC - PubMed
Hughes 2004
    1. Hughes JR, Keely J, Naud S. Shape of the relapse curve and long-term abstinence among untreated smokers. Addiction 2004;99(1):29-38. - PubMed
Jiang 2016
    1. Jiang N, Chen J, Wang MP, McGhee SM, Kwong AC, Lai VW, et al. Electronic cigarette awareness and use among adults in Hong Kong. Addictive Behaviors 2016;52:34-8. - PubMed
Levett  2023
    1. Levett JY, Filion KB, Reynier P, Prell C, Eisenberg MJ. Efficacy and Safety of E-Cigarette Use for Smoking Cessation: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. American Journal of Medicine 2023;136(8):804-13. - PubMed
Levin 1993
    1. Levin ED, Behm F, Carnahan E, LeClair R, Shipley R, Rose JE. Clinical trials using ascorbic acid aerosol to aid smoking cessation. Drug and Alcohol Dependence 1993;33(3):211-23. - PubMed
Liber 2023
    1. Liber AC, Knoll M, Cadham CJ, Issabakhsh M, Oh H, Cook S. The role of flavored electronic nicotine delivery systems in smoking cessation: A systematic review. Drug and Alcohol Dependence Reports June 2023;7:100143. [DOI: 10.1016/j.dadr.2023.100143] - DOI - PMC - PubMed
Lindson 2022
    1. Lindson N, Butler AR, Liber A, Levy D, Barnett P, Theodoulou A, et al. An exploration of flavours in studies of e-cigarettes for smoking cessation: secondary analyses of a systematic review with meta-analyses. Addiction 2022;online first:Nov 18. [DOI: ] - PMC - PubMed
Lindson 2023a
    1. Lindson N, Theodoulou A, Ordóñez-Mena JM, Fanshawe TR, Sutton AJ, Livingstone-Banks J, et al. Pharmacological and electronic cigarette interventions for smoking cessation in adults: component network meta‐analyses. Cochrane Database of Systematic Reviews 2023, Issue 9. Art. No: CD015226. [DOI: 10.1002/14651858.CD015226.pub2] - DOI - PMC - PubMed
Lindson 2023b
    1. Lindson N, Butler A, McRobbie H, Bullen C, Begh R, Theodoulou A et al. Update to protocol of the Cochrane review of electronic cigarettes for smoking cessation. OSF 2023;July:1-3. [DOI: 10.17605/OSF.IO/ZWGSK] - DOI
Livingstone‐Banks 2023
    1. Livingstone-Banks J, Fanshawe TR, Thomas KH, Theodoulou A, Hajizadeh A, Hartman L, et al. Nicotine receptor partial agonists for smoking cessation. Cochrane Database of Systematic Reviews 2023, Issue 6. Art. No: CD006103. [DOI: 10.1002/14651858.CD006103.pub9] - DOI - PMC - PubMed
Martinez‐Morata 2021
    1. Martinez-Morata I, Sanchez TR, Shimbo D, Navas-Acien A. Electronic cigarette use and blood pressure endpoints: a systematic review. Current Hypertension Reports 2021;23(1):1. - PMC - PubMed
McDonald 2020
    1. McDonald CF, Jones S, Beckert L, Bonevski B, Buchanan T, Bozier J, et al. Electronic cigarettes: a position statement from the Thoracic Society of Australia and New Zealand. Respirology 2020 [Epub ahead of print]. - PMC - PubMed
McNeill 2021
    1. McNeill A, Brose LS, Calder R, Bauld L, Robson D. Vaping in England: an evidence update including vaping for smoking cessation, February 2021: a report commissioned by Public Health England London, UK: Public Health England. assets.publishing.service.gov.uk/government/uploads/system/uploads/attac... (accessed prior to 3 November 2022).
McNeill 2022
    1. McNeill A, Simonavičius E, Brose LS, Taylor E, East K, Zuikova E, et al. Nicotine vaping in England: an evidence update including health risks and perceptions. A report commissioned by the Office for Health Improvement and Disparities. London: Office for Health Improvement and Disparities. assets.publishing.service.gov.uk/government/uploads/system/uploads/attac... (accessed prior to 3 November 2022).
McRobbie 2016
    1. McRobbie H, Przulj D, Smith KM, Cornwall D. Complementing the standard multicomponent treatment for smokers with denicotinized cigarettes: a randomized trial. Nicotine & Tobacco Research 2016;18(5):1134-41. - PubMed
Meng 2023
    1. Meng XC, Guo XX, Peng ZY, Wang C, Liu R. Acute Effects of Electronic Cigarettes on Vascular Endothelial Function: a Systematic Review and Meta-analysis of Randomized Controlled Trials. Eur J Prev Cardiol 2023 March;30(5):425-35. [DOI: 10.1093/eurjpc/zwac248] - DOI - PubMed
NASEM 2018
    1. National Academies of Sciences, Engineering, and Medicine, Health and Medicine Division, Board on Population Health and Public Health Practice. Public Health Consequences of E-Cigarettes. Washington (DC): National Academies Press (US), 2018.
NICE 2021
    1. NICE, National Institute for Health and Care Excellence. Tobacco: preventing uptake, promoting quitting and treating dependence. NICE Guideline 2021, updated 2023;NG209(London):UK. - PubMed
Notley 2018a
    1. Notley C, Colllins R. Redefining smoking relapse as recovered social identity - secondary qualitative analysis of relapse narratives. Journal of Substance Use 2018;23(6):660-6.
Notley 2018b
    1. Notley C, Ward E, Dawkins L, Holland R. The unique contribution of e-cigarettes for tobacco harm reduction in supporting smoking relapse prevention. Harm Reduct J 2018;15(1):31. - PMC - PubMed
Owen 2019
    1. Owen RK, Bradbury N, Xin Y, Cooper N, Sutton A. MetaInsight: An interactive web-based tool for analyzing, interrogating, and visualizing network meta-analyses using R-shiny and netmeta. Research Synthesis Methods 26th July 2019;10(4):569-581. - PMC - PubMed
Palipudi 2016
    1. Palipudi KM, Mbulo L, Morton J, Bunnell R, Blutcher-Nelson G, Kosen S, et al. Awareness and current use of electronic cigarettes in Indonesia, Malaysia, Qatar, and Greece: findings from 2011–2013 global adult tobacco surveys. Nicotine & Tobacco Research 2016;18(4):501-7. - PMC - PubMed
Patnode 2021
    1. Patnode CD, Henderson JT, Coppola EL, Melnikow J, Durbin S, Thomas RG. Interventions for tobacco cessation in adults, including pregnant persons: updated evidence report and systematic review for the US Preventive Services Task Force. JAMA 2021;325(3):280-98. - PubMed
Perkins 2010
    1. Perkins KA, Karelitz JL, Conklin CA, Sayette MA, Giedgowd GE. Acute negative affect relief from smoking depends on the affect situation and measure but not on nicotine. Biological Psychology 2010;67(8):707-14. - PMC - PubMed
Pickworth 1999
    1. Pickworth WB, Fant RV, Nelson RA, Rohrer MS, Henningfield JE. Pharmacodynamic effects of new de-nicotinized cigarettes. Nicotine & Tobacco Research 1999;1(4):357-64. - PubMed
Pound 2021
    1. Pound CM, Zhang JZ, Kodua AT, Sampson M. Smoking cessation in individuals who use vaping as compared with traditional nicotine replacement therapies: a systematic review and meta-analysis. BMJ Open 2021;11(2):e044222. [DOI: 10.1136/bmjopen-2020-044222] - DOI - PMC - PubMed
Przulj 2013
    1. Przulj D, McRobbie H, Hajek P. The effect of sensorimotor replacement on smoking cessation and craving. Open Addiction Journal 2013;5:41-50.
Quigley 2021
    1. Quigley JM, Walsh C, Lee C, Long J, Kennelly H, McCarthy A, et al. Efficacy and safety of electronic cigarettes as a smoking cessation intervention: a systematic review and network meta-analysis. Tobacco Prevention & Cessation 2021;7(69):1-14. [DOI: 10.18332/tpc/143077] - DOI - PMC - PubMed
RCP 2016
    1. Tobacco Advisory Group of the Royal College of Physicians. Nicotine Without Smoke—Tobacco Harm Reduction. London: Royal College of Physicians, 2016.
Review Manager 2022 [Computer program]
    1. Review Manager Web (RevMan Web). Version 4.12.0. The Cochrane Collaboration, 2022. Available at revman.cochrane.org.
Rose 1985
    1. Rose JE, Tashkin DP, Ertle A, Zinser MC, Lafer R. Sensory blockade of smoking satisfaction. Pharmacology Biochemistry & Behavior 1985;23(2):289-93. - PubMed
Rose 1993
    1. Rose JE, Behm FM, Levin ED. Role of nicotine dose and sensory cues in the regulation of smoke intake. Pharmacology Biochemistry & Behavior 1993;44(4):891-900. - PubMed
Rose 1994
    1. Rose JE, Behm FM. Inhalation of vapor from black pepper extract reduces smoking withdrawal symptoms. Drug and Alcohol Dependence 1994;34(3):225-9. - PubMed
Rose 2000
    1. Rose JE, Behm FM, Westman EC, Johnson M. Dissociating nicotine and nonnicotine components of cigarette smoking. Pharmacology Biochemistry & Behavior 2000;67(1):71-81. - PubMed
Rose 2006
    1. Rose JE. Nicotine and nonnicotine factors in cigarette addiction. Psychopharmacology 2006;184(3-4):274-85. - PubMed
Schneider 2001
    1. Schneider NG, Olmstead RE, Franzon MA, Lunell E. The nicotine inhaler: clinical pharmacokinetics and comparison with other nicotine treatments. Clinical Pharmcokinetics 2001;40(9):661-84. - PubMed
Siddiqi 2023
    1. Siddiqi TJ, Rashid AM, Siddiqi AK, Anwer A, Usman MS, Sakhi H et al. Association of Electronic Cigarette Exposure on Cardiovascular Health: A Systematic Review and Meta-Analysis. Curr Probl Cardiol 2023 Sept;48(9):101748. [DOI: 10.1016/j.cpcardiol.2023.101748] - DOI - PubMed
Smets 2019
    1. Smets J, Baeyens F, Chaumont M, Adriaens K, Van Gucht D. When less is more: vaping low-nicotine vs. high-nicotine e-liquid is compensated by increased wattage and higher liquid consumption. International Journal of Environmental Research and Public Health 2019;16(5):723. - PMC - PubMed
Talih 2020
    1. Talih S, Salman R, El-Hage R, Karam E, Salam S, Karaoghlanian N, et al. A comparison of the electrical characteristics, liquid composition, and toxicant emissions of JUUL USA and JUUL UK e-cigarettes. Scientific Reports 2020;10(1):7322. - PMC - PubMed
Tattan‐Birch 2020
    1. Tattan-Birch H, Brown J, Shahab L, Jackson SE. Association of the US outbreak of vaping-associated lung injury with perceived harm of e-cigarettes compared with cigarettes. JAMA Network Open 2020;3(6):e206981. - PMC - PubMed
Tattan‐Birch 2022
    1. Tattan-Birch H, Jackson SE, Kock L, Dockrell M, Brown J. Rapid growth in disposable e-cigarette vaping among young adults in Great Britain from 2021 to 2022: a repeat cross-sectional survey. Addiction 2023;118(2):382-6. [DOI: 10.1111/add.16044] - DOI - PMC - PubMed
Taylor 2023
    1. Taylor E, Simonavicius E, McNeill A, Brose LS, East K, Marczylo T et al. Exposure to Tobacco Specific Nitrosamines among people who vape, smoke or do neither. A Systematic Review and Meta Analysis. Nicotine and Tobacco Research 2023;24 Aug:Epub. [DOI: 10.1093/ntr/ntad156] - DOI - PMC - PubMed
Theodoulou 2023
    1. Theodoulou A, Chepkin SC, Ye W, Fanshawe TR, Bullen C, Hartmann-Boyce J, et al. Different doses, durations and modes of delivery of nicotine replacement therapy for smoking cessation. Cochrane Database of Systematic Reviews 2023, Issue 6. Art. No: CD013308. [DOI: 10.1002/14651858.CD013308.pub2] - DOI - PMC - PubMed
Thiem 2023
    1. Thiem DGE, Donkiewicz P, Rejaey R, Wiesmann-Imilowski N, Deschner J, Al-Nawas B et al. The impact of electronic and conventional cigarettes on periodontal health-a systematic review and meta-analysis. Clinical Oral Investigations 2023 Sept;27(9):4911-28. [DOI: 10.1007/s00784-023-05162-4] - DOI - PMC - PubMed
Thomas 2022
    1. Thomas KH, Dalili MN, López‐López JA, Keeney E, Phillippo DM, Munafò MR, et al. Comparative clinical effectiveness and safety of tobacco cessation pharmacotherapies and electronic cigarettes: a systematic review and network meta‐analysis of randomized controlled trials. Addiction 2022;117(4):861-76. - PMC - PubMed
USPFTS 2021
    1. US Preventive Services Task Force. Interventions for tobacco smoking cessation in adults,including pregnant persons. www.uspreventiveservicestaskforce.org/uspstf/recommendation/tobacco-use-... (accessed prior to 3 November 2022). - PubMed
Vanderkam 2022
    1. Vanderkam P, Bonneau A, Kinouani S, Dzeraviashka P, Castera P, Besnier M, et al. Duration of the effectiveness of nicotine electronic cigarettes on smoking cessation and reduction: systematic review and meta-analysis. Front Psychiatry 2022;4(13):915946. - PMC - PubMed
Vansickel 2010
    1. Vansickel AR, Cobb CO, Weaver MF, Eissenberg TE. A clinical laboratory model for evaluating the acute effects of electronic "cigarettes": nicotine delivery profile and cardiovascular and subjective effects. Cancer Epidemiology, Biomarkers & Prevention 2010;19(8):1945-53. [DOI: 10.1158/1055-9965.EPI-10-0288] - DOI - PMC - PubMed
Vansickel 2012
    1. Vansickel AR, Weaver MF, Eissenberg T. Clinical laboratory assessment of the abuse liability of an electronic cigarette. Addiction 2012;107(8):1483-500. [DOI: 10.1111/j.1360-0443.2012.03791.x] - DOI - PMC - PubMed
Vansickel 2013
    1. Vansickel AR, Eissenberg T. Electronic cigarettes: effective nicotine delivery after acute administration. Nicotine & Tobacco Research 2013;15(1):267-70. [DOI: 10.1093/ntr/ntr316] - DOI - PMC - PubMed
Walker 2012
    1. Walker N, Howe C, Bullen C, Grigg M, Glover M, McRobbie H, et al. The combined effect of very low nicotine content cigarettes, used as an adjunct to usual Quitline care (nicotine replacement therapy and behavioural support), on smoking cessation: a randomized controlled trial. Addiction 2012;107(10):1857-67. - PubMed
Wang 2021
    1. Wang RJ, Bhadriraju S, Glantz SA. E-cigarette use and adult cigarette smoking cessation: a meta-analysis. American Journal of Public Health 2021;111:230-46. - PMC - PubMed
Westman 1995
    1. Westman EC, Behm FM, Rose JE. Airway sensory replacement combined with nicotine replacement for smoking cessation. A randomized, placebo-controlled trial using a citric acid inhaler. Chest 1995;107(5):1358-64. - PubMed
Westman 1996
    1. Westman EC, Behm FM, Rose JE. Dissociating the nicotine and airway sensory effects of smoking. Pharmacology Biochemistry & Behavior 1996;53(2):309-15. - PubMed
Wilson 2021
    1. Wilson N, Summers JA, Ait Ouakrim D, Hoek J, Edwards R, Blakely T. Improving on estimates of the potential relative harm to health from using modern ENDS (vaping) compared to tobacco smoking. BMC Public Health 2021;21(1):2038. - PMC - PubMed
Yingst 2019a
    1. Yingst JM, Foulds J, Veldheer S, Hrabovsky S, Trushin N, Eissenberg TT, et al. Nicotine absorption during electronic cigarette use among regular users. PLOS One 2019;14(7):e0220300. - PMC - PubMed
Yingst 2019b
    1. Yingst JM, Hrabovsky S, Hobkirk A, Trushin N, Richie JP Jr, Foulds J. Nicotine absorption profile among regular users of a pod-based electronic nicotine delivery system. JAMA Network Open 2019;2(11):e1915494. - PMC - PubMed
Zhang 2021
    1. Zhang YY, Bu FL, Dong F, Wang JH, Zhu SJ, Zhang XW, et al. The effect of e-cigarettes on smoking cessation and cigarette smoking initiation: an evidence-based rapid review and meta-analysis. Tobacco Induced Diseases 2021;19:04. [DOI: 10.18332/tid/131624] - DOI - PMC - PubMed

References to other published versions of this review

Hartmann‐Boyce 2016
    1. Hartmann-Boyce J, McRobbie H, Bullen C, Begh R, Stead LF, Hajek P. Electronic cigarettes for smoking cessation. Cochrane Database of Systematic Reviews 2016, Issue 9. Art. No: CD010216. [DOI: 10.1002/14651858.CD010216.pub3] - DOI - PMC - PubMed
Hartmann‐Boyce 2020
    1. Hartmann-Boyce J, McRobbie H, Lindson N, Bullen C, Begh R, Theodoulou A, et al. Electronic cigarettes for smoking cessation. Cochrane Database of Systematic Reviews 2020, Issue 10. Art. No: CD010216. [DOI: 10.1002/14651858.CD010216.pub4] - DOI - PMC - PubMed
Hartmann‐Boyce 2021a
    1. Hartmann-Boyce J, McRobbie H, Butler AR, Lindson N, Bullen C, Begh R, et al. Electronic cigarettes for smoking cessation. Cochrane Database of Systematic Reviews 2021, Issue 4. Art. No: CD010216. [DOI: 10.1002/14651858.CD010216.pub5] - DOI - PMC - PubMed
McRobbie 2012
    1. McRobbie H, Bullen C, Hajek P. Electronic cigarettes for smoking cessation and reduction. Cochrane Database of Systematic Reviews 2012, Issue 11. Art. No: CD010216. [DOI: 10.1002/14651858.CD010216] - DOI - PubMed
McRobbie 2014
    1. McRobbie H, Bullen C, Hartmann-Boyce J, Hajek P. Electronic cigarettes for smoking cessation and reduction. Cochrane Database of Systematic Reviews 2014, Issue 12. Art. No: CD010216. [DOI: 10.1002/14651858.CD010216.pub2] - DOI - PubMed

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