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. 2019 Sep 30;9(9):CD013183.
doi: 10.1002/14651858.CD013183.pub2.

Smoking reduction interventions for smoking cessation

Nicola Lindson  1 , Elias Klemperer, Bosun Hong, José M Ordóñez-Mena, Paul Aveyard
Affiliations

Smoking reduction interventions for smoking cessation

Nicola Lindson et al. Cochrane Database Syst Rev. .

Abstract

Background: The standard way most people are advised to stop smoking is by quitting abruptly on a designated quit day. However, many people who smoke have tried to quit many times and may like to try an alternative method. Reducing smoking behaviour before quitting could be an alternative approach to cessation. However, before this method can be recommended it is important to ensure that abrupt quitting is not more effective than reducing to quit, and to determine whether there are ways to optimise reduction methods to increase the chances of cessation.

Objectives: To assess the effect of reduction-to-quit interventions on long-term smoking cessation.

Search methods: We searched the Cochrane Tobacco Addiction Group Specialised Register, MEDLINE, Embase and PsycINFO for studies, using the terms: cold turkey, schedul*, cut* down, cut-down, gradual*, abrupt*, fading, reduc*, taper*, controlled smoking and smoking reduction. We also searched trial registries to identify unpublished studies. Date of the most recent search: 29 October 2018.

Selection criteria: Randomised controlled trials in which people who smoked were advised to reduce their smoking consumption before quitting smoking altogether in at least one trial arm. This advice could be delivered using self-help materials or behavioural support, and provided alongside smoking cessation pharmacotherapies or not. We excluded trials that did not assess cessation as an outcome, with follow-up of less than six months, where participants spontaneously reduced without being advised to do so, where the goal of reduction was not to quit altogether, or where participants were advised to switch to cigarettes with lower nicotine levels without reducing the amount of cigarettes smoked or the length of time spent smoking. We also excluded trials carried out in pregnant women.

Data collection and analysis: We followed standard Cochrane methods. Smoking cessation was measured after at least six months, using the most rigorous definition available, on an intention-to-treat basis. We calculated risk ratios (RRs) and 95% confidence intervals (CIs) for smoking cessation for each study, where possible. We grouped eligible studies according to the type of comparison (no smoking cessation treatment, abrupt quitting interventions, and other reduction-to-quit interventions) and carried out meta-analyses where appropriate, using a Mantel-Haenszel random-effects model. We also extracted data on quit attempts, pre-quit smoking reduction, adverse events (AEs), serious adverse events (SAEs) and nicotine withdrawal symptoms, and meta-analysed these where sufficient data were available.

Main results: We identified 51 trials with 22,509 participants. Most recruited adults from the community using media or local advertising. People enrolled in the studies typically smoked an average of 23 cigarettes a day. We judged 18 of the studies to be at high risk of bias, but restricting the analysis only to the five studies at low or to the 28 studies at unclear risk of bias did not significantly alter results.We identified very low-certainty evidence, limited by risk of bias, inconsistency and imprecision, comparing the effect of reduction-to-quit interventions with no treatment on cessation rates (RR 1.74, 95% CI 0.90 to 3.38; I2 = 45%; 6 studies, 1599 participants). However, when comparing reduction-to-quit interventions with abrupt quitting (standard care) we found evidence that neither approach resulted in superior quit rates (RR 1. 01, 95% CI 0.87 to 1.17; I2 = 29%; 22 studies, 9219 participants). We judged this estimate to be of moderate certainty, due to imprecision. Subgroup analysis provided some evidence (P = 0.01, I2 = 77%) that reduction-to-quit interventions may result in more favourable quit rates than abrupt quitting if varenicline is used as a reduction aid. Our analysis comparing reduction using pharmacotherapy with reduction alone found low-certainty evidence, limited by inconsistency and imprecision, that reduction aided by pharmacotherapy resulted in higher quit rates (RR 1. 68, 95% CI 1.09 to 2.58; I2 = 78%; 11 studies, 8636 participants). However, a significant subgroup analysis (P < 0.001, I2 = 80% for subgroup differences) suggests that this may only be true when fast-acting NRT or varenicline are used (both moderate-certainty evidence) and not when nicotine patch, combination NRT or bupropion are used as an aid (all low- or very low-quality evidence). More evidence is likely to change the interpretation of the latter effects.Although there was some evidence from within-study comparisons that behavioural support for reduction to quit resulted in higher quit rates than self-help resources alone, the relative efficacy of various other characteristics of reduction-to-quit interventions investigated through within- and between-study comparisons did not provide any evidence that they enhanced the success of reduction-to-quit interventions. Pre-quit AEs, SAEs and nicotine withdrawal symptoms were measured variably and infrequently across studies. There was some evidence that AEs occurred more frequently in studies that compared reduction using pharmacotherapy versus no pharmacotherapy; however, the AEs reported were mild and usual symptoms associated with NRT use. There was no clear evidence that the number of people reporting SAEs, or changes in withdrawal symptoms, differed between trial arms.

Authors' conclusions: There is moderate-certainty evidence that neither reduction-to-quit nor abrupt quitting interventions result in superior long-term quit rates when compared with one another. Evidence comparing the efficacy of reduction-to-quit interventions with no treatment was inconclusive and of low certainty. There is also low-certainty evidence to suggest that reduction-to-quit interventions may be more effective when pharmacotherapy is used as an aid, particularly fast-acting NRT or varenicline (moderate-certainty evidence). Evidence for any adverse effects of reduction-to-quit interventions was sparse, but available data suggested no excess of pre-quit SAEs or withdrawal symptoms. We downgraded the evidence across comparisons due to risk of bias, inconsistency and imprecision. Future research should aim to match any additional components of multicomponent reduction-to-quit interventions across study arms, so that the effect of reduction can be isolated. In particular, well-conducted, adequately-powered studies should focus on investigating the most effective features of reduction-to-quit interventions to maximise cessation rates.

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Conflict of interest statement

BH has no known conflicts of interest.

EK has no known conflicts of interest. EK was an author of one included study (Klemperer 2017). They did not carry out data extraction or risk of bias assessment for this study.

JMOM has no known conflicts of interest.

NL has no known conflicts of interest. NL was an author of one included study (Lindson‐Hawley 2016b). They did not carry out data extraction or risk of bias assessment for this study.

PA has no known conflicts of interest. PA was an author of two included studies (Farley 2017; Lindson‐Hawley 2016b) They did not carry out data extraction or risk of bias assessment for those studies.

Figures

1
1
Study flow diagram.
2
2
Risk of bias summary: review authors' judgements about each risk of bias item for each included study.
3
3
Funnel plot of comparison: 2 Reduction to quit versus abrupt quitting, outcome: 2.1 Abstinence.
4
4
Funnel plot of comparison: 3 Reduction + pharma vs reduction alone, outcome: 3.1 Abstinence.
1.1
1.1. Analysis
Comparison 1 Reduction to quit versus no treatment, Outcome 1 Abstinence.
1.2
1.2. Analysis
Comparison 1 Reduction to quit versus no treatment, Outcome 2 Abstinence: subgrouped by pre‐quit pharma in reduction arm.
1.3
1.3. Analysis
Comparison 1 Reduction to quit versus no treatment, Outcome 3 Quit attempts.
1.4
1.4. Analysis
Comparison 1 Reduction to quit versus no treatment, Outcome 4 Pre‐quit reduction in cpd of at least 50%.
1.5
1.5. Analysis
Comparison 1 Reduction to quit versus no treatment, Outcome 5 Pre‐quit SAEs.
2.1
2.1. Analysis
Comparison 2 Reduction to quit versus abrupt quitting, Outcome 1 Abstinence.
2.2
2.2. Analysis
Comparison 2 Reduction to quit versus abrupt quitting, Outcome 2 Abstinence: sensitivity analysis removing studies with lower‐intensity abrupt arms.
2.3
2.3. Analysis
Comparison 2 Reduction to quit versus abrupt quitting, Outcome 3 Abstinence: subgrouped by pre‐quit pharma in reduction arm.
2.4
2.4. Analysis
Comparison 2 Reduction to quit versus abrupt quitting, Outcome 4 Abstinence: subgrouped by set quit date.
2.5
2.5. Analysis
Comparison 2 Reduction to quit versus abrupt quitting, Outcome 5 Abstinence: subgrouped by cpd vs sfp reduction.
2.6
2.6. Analysis
Comparison 2 Reduction to quit versus abrupt quitting, Outcome 6 Abstinence: subgrouped by structured vs unstructured reduction advised.
2.7
2.7. Analysis
Comparison 2 Reduction to quit versus abrupt quitting, Outcome 7 Abstinence: subgrouped by length of the reduction period.
2.8
2.8. Analysis
Comparison 2 Reduction to quit versus abrupt quitting, Outcome 8 Abstinence: subgrouped by reduction goal.
2.9
2.9. Analysis
Comparison 2 Reduction to quit versus abrupt quitting, Outcome 9 Quit attempts.
2.10
2.10. Analysis
Comparison 2 Reduction to quit versus abrupt quitting, Outcome 10 Pre‐quit reduction of at least 50%.
2.11
2.11. Analysis
Comparison 2 Reduction to quit versus abrupt quitting, Outcome 11 Pre‐quit reduction in cpd.
2.12
2.12. Analysis
Comparison 2 Reduction to quit versus abrupt quitting, Outcome 12 Pre‐quit reduction in carbon monoxide.
2.13
2.13. Analysis
Comparison 2 Reduction to quit versus abrupt quitting, Outcome 13 Pre‐quit reduction in cotinine.
2.14
2.14. Analysis
Comparison 2 Reduction to quit versus abrupt quitting, Outcome 14 Pre‐quit SAEs.
3.1
3.1. Analysis
Comparison 3 Reduction + pharmacotherapy versus reduction alone, Outcome 1 Abstinence.
3.2
3.2. Analysis
Comparison 3 Reduction + pharmacotherapy versus reduction alone, Outcome 2 Quit attempts.
3.3
3.3. Analysis
Comparison 3 Reduction + pharmacotherapy versus reduction alone, Outcome 3 Pre‐quit cpd reduction of ≥ 50% or 75%.
3.4
3.4. Analysis
Comparison 3 Reduction + pharmacotherapy versus reduction alone, Outcome 4 Pre‐quit reduction in cpd.
3.5
3.5. Analysis
Comparison 3 Reduction + pharmacotherapy versus reduction alone, Outcome 5 Pre‐quit reduction in carbon monoxide.
3.6
3.6. Analysis
Comparison 3 Reduction + pharmacotherapy versus reduction alone, Outcome 6 Pre‐quit AEs.
3.7
3.7. Analysis
Comparison 3 Reduction + pharmacotherapy versus reduction alone, Outcome 7 Pre‐quit SAEs.
4.1
4.1. Analysis
Comparison 4 Modality of reduction support, Outcome 1 Abstinence.
4.2
4.2. Analysis
Comparison 4 Modality of reduction support, Outcome 2 Pre‐quit reduction in cpd.
5.1
5.1. Analysis
Comparison 5 Length of reduction, Outcome 1 Abstinence.
5.2
5.2. Analysis
Comparison 5 Length of reduction, Outcome 2 Pre‐quit cpd reduction ≥ 50%.
6.1
6.1. Analysis
Comparison 6 More structured vs less structured reduction, Outcome 1 Abstinence.
6.2
6.2. Analysis
Comparison 6 More structured vs less structured reduction, Outcome 2 Quit attempts.
6.3
6.3. Analysis
Comparison 6 More structured vs less structured reduction, Outcome 3 Pre‐quit reduction in cpd.
7.1
7.1. Analysis
Comparison 7 Additional behavioural SC components, Outcome 1 Abstinence.
7.2
7.2. Analysis
Comparison 7 Additional behavioural SC components, Outcome 2 Pre‐quit reduction in cpd.
8.1
8.1. Analysis
Comparison 8 Behavioural reduction versus nicotine fading, Outcome 1 Abstinence.
8.2
8.2. Analysis
Comparison 8 Behavioural reduction versus nicotine fading, Outcome 2 Pre‐quit reduction in cotinine.
9.1
9.1. Analysis
Comparison 9 Other comparisons, Outcome 1 Abstinence.
9.2
9.2. Analysis
Comparison 9 Other comparisons, Outcome 2 Pre‐quit reduction in cpd.
9.3
9.3. Analysis
Comparison 9 Other comparisons, Outcome 3 Pre‐quit reduction in CO.
See this image and copyright information in PMC

Update of

  • doi: 10.1002/14651858.CD013183

References

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Ostroff 2014 {published data only}
    1. NCT00575718. Smoking cessation intervention for cancer patients. clinicaltrials.gov/ct2/show/NCT00575718 (first received 18 December 2007).
    1. Ostroff J, Burkhalter J, Cinciripini P, Li Y, Shiyko M, Lam C, et al. Randomized trial of a pre‐surgical, scheduled reduced smoking intervention for patients newly diagnosed with cancer. Psycho‐oncology 2013;22(S2):74‐75. - PMC - PubMed
    1. Ostroff JS, Burkhalter JE, Cinciripini PM, Li Y, Shiyko MP, Lam CY, et al. Randomized trial of a presurgical scheduled reduced smoking intervention for patients newly diagnosed with cancer. Health Psychology 2014;33(7):737‐47. - PMC - PubMed
    1. Sloan E, Lord‐Bessen J, Hollan S, Li Y, Burkhalter J, Furberg A, et al. An analysis of treatment implementation fidelity as a possible explanation for null findings in a smoking cessation trial. Society for Research on Nicotine and Tobacco 18th Annual Meeting; 2012 Mar 13‐16; Houston, USA. 2012:101. [POS3‐32]
Perez‐Milena 2012 {published data only}
    1. Perez‐Milena A, Navarreteguillen AB, Mesa‐Gallardo MI, Martinez Perez R, Leal‐Helmling FJ, Perez‐Fuentes C. Efficiency of two motivational interventions for adolescent smokers (brief and intensive) conducted in High Schools [Eficiencia de dos intervenciones motivacionales para la deshabituación tabáquica en adolescentes (breve e intensiva) realizadas en Institutos de Educación Secundaria]. Adicciones 2012;24(3):191‐9. - PubMed
Rennard 2006 {published data only}
    1. Rennard SI, Glover E, Leischow S, Daughton DM, Glover P, Muramoto M. Efficacy of nicotine inhaler in smoking reduction. Nicotine & Tobacco Research 2002;4(3):380. - PubMed
    1. Rennard SI, Glover ED, Leischow S, Daughton DM, Glover PN, Muramoto M, et al. Efficacy of the nicotine inhaler in smoking reduction: A double‐blind, randomized trial. Nicotine & Tobacco Research 2006;8(4):555‐64. - PubMed
Riley 2001 {published data only}
    1. Jerome A, Fiero PL, Behar A, Bensur A. Combining scheduled, gradual reduction with nicotine replacement. Society for Research on Nicotine and Tobacco Fifth Annual Meeting; 1999 Mar 5‐7; San Diego, USA. 1999. [PO B50]
    1. Riley W, Behar A, Jerome A, Weil WS. Computerized scheduled gradual reduction of smoking prior to nicotine patch use: evidence of additive efficacy. Society for Research on Nicotine and Tobacco 7th Annual Meeting; 2001 Mar 20‐23 Seattle, USA. 2001:74. [PO3 28]
Riley 2005 {published data only}
    1. Riley W. Computerized scheduling of nicotine nasal spray. USA: LifeSign; 2005. Study ID: R44DA013062.
    1. Riley WT, Behar A, Shields R, Kelleher K, Vasiliadis M. Effects of a scheduled gradual crossover of cigarettes and nicotine nasal spray. Society for Research on Nicotine and Tobacco 11th Annual Meeting; 2005 Mar 20‐23; Prague, Czech Republic. 2005.
Rohsenow 2016 {published data only}
    1. Martin RA, Rohsenow D, Tidey JW, Colby S, Monti P. Treating smokers in substance treatment with contingent vouchers, nicotine replacement and brief advice adapted for sobriety settings. Drug and Alcohol Dependence 2015;156:e140‐1. - PMC - PubMed
    1. Rohsenow DJ, Martin RA, Tidey JW, Colby SM, Monti PM. Treating smokers in substance treatment with contingent vouchers, nicotine replacement and brief advice adapted for sobriety settings. Journal of Substance Abuse Treatment 2016;72:72‐9. - PMC - PubMed
Ruther 2018 {published data only}
    1. Ruther T, Kiss A, Eberhardt K, Linhardt A, Kroger C, Pogarell O. Evaluation of the cognitive behavioral smoking reduction program "Smoke_less": a randomized controlled trial. European Archives of Psychiatry and Clinical Neuroscience 2018;268(3):269‐77. - PubMed
Shiffman 2009 {published data only}
    1. Shiffman S, Dresler CM, Norton M, Strahs K. Using nicotine gum to assist quitting by gradual reduction. Society for Research on Nicotine and Tobacco 12th Annual Meeting; 2006 Feb 15‐18, Orlando, USA. 2006:14. [SYM10D]
    1. Shiffman S, Ferguson SG, Strahs KR. Quitting by gradual smoking reduction using nicotine gum: a randomized controlled trial. American Journal of Preventive Medicine 2009;36(2):96‐104. - PubMed
Wang 2017 {published data only}
    1. Wang MP, Li WH, Cheung YT, Lam OB, Wu Y, Kwong AC, et al. Brief advice on smoking reduction versus abrupt quitting for smoking cessation in Chinese smokers: a cluster randomized controlled trial. Nicotine & Tobacco Research 2017;20(1):67‐72. - PubMed
Wennike 2003 {published data only}
    1. Wennike P, Danielsson T, Landfeldt B, Westin A, Tonnesen P. Smoking reduction promotes smoking cessation: results from a double blind, randomized, placebo‐controlled trial of nicotine gum with 2‐year follow‐up. Addiction 2003;98(10):1395‐402. - PubMed
Wu 2017 {published data only}
    1. Wu L, He Y, Jiang B, Zhang D, Tian H, Zuo F, et al. The effect of a very brief smoking‐reduction intervention in smokers who have no intention to quit: study protocol for a randomized controlled trial. BMC Public Health 2015;15:418‐23. - PMC - PubMed
    1. Wu L, He Y, Jiang B, Zhang D, Tian H, Zuo F, et al. Very brief physician advice and supplemental proactive telephone calls to promote smoking reduction and cessation in Chinese male smokers with no intention to quit: a randomized trial. Addiction 2017;112(11):2032‐40. - PubMed

References to studies excluded from this review

ACTRN12609000482268 {published data only}
    1. ACTRN12609000482268. Randomised controlled trial of Zonnic and nicotine patch (ZAP) in smoking cessation [Randomised placebo‐controlled trial of Zonnic and nicotine patch in heavy smokers for smoking cessation]. www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12609000482268 (First received 18 June 2009).
ACTRN12617000905369 {published data only}
    1. ACTRN12617000905369. Feasibility of electronic nicotine devices for smoking cessation with alcohol and other drug treatment clients [The QuitENDs Study: a feasibility pilot study of electronic nicotine devices for smoking cessation with alcohol and other drug treatment clients]. www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=373092 (First received 20 June 2017).
Applegate 2004 {published data only}
    1. Applegate BW, Riley WT, Sowell A. A comparison of computer‐assisted scheduled gradual reduction vs. self help in unmotivated smokers. Society for Research on Nicotine and Tobacco 10th Annual Meeting; 2004 Feb 18‐21; Phoenix, USA. 2004:41. [POS1‐028]
Armitage 2007 {published data only}
    1. Armitage CJ. Efficacy of a brief worksite intervention to reduce smoking: the roles of behavioral and implementation intentions. Journal of Occupational Health Psychology 2007;12(4):376‐90. [DOI: 10.1037/1076-8998.12.4.376] - DOI - PubMed
Atwood 1975 {published data only}
    1. Atwood JT. The Influence of Differential Treatment Goals on the Success of a Behavior Modification Program for Smokers [thesis]. USA: Dissertation Abstracts International, 1975.
Audrain McGovern 2011 {published data only}
    1. Audrain‐McGovern J, Stevens S, Murray PJ, Kinsman S, Zuckoff A, Pletcher J, et al. The efficacy of motivational interviewing versus brief advice for adolescent smoking behavior change. Pediatrics 2011;128(1):e101‐e111. [DOI: 10.1542/peds.2010-2174] - DOI - PubMed
Aveyard 2011 {published data only}
    1. Aveyard P, Begh R, Sheikh A, Amos A. Promoting smoking cessation through smoking reduction during Ramadan. Addiction 2011;106(8):1379‐80. [DOI: ] - PubMed
Aveyard 2014 {published data only}
    1. Aveyard P, Lindson‐Hawley N, Hastings G, Andrade M. Should smokers be advised to cut down as well as quit?. BMJ 2014;348:g2787. [DOI: ] - PubMed
Baker 2006 {published data only}
    1. Baker A, Richmond R, Haile M, Lewin TJ, Carr VJ, Taylor RL, et al. A randomized controlled trial of a smoking cessation intervention among people with a psychotic disorder. American Journal of Psychiatry 2006;163(11):1934‐42. [DOI: 10.1176/appi.ajp.163.11.1934] - DOI - PubMed
    1. Baker A, Richmond R, Kay‐Lambkin F, Lewin TJ, Carr VJ. Randomized controlled trial of a smoking cessation intervention among people with a psychotic disorder: 3‐year follow‐up. Society for Research on Nicotine and Tobacco 13th Annual Meeting; 2007 Feb 21‐24, Austin, USA. 2007. [PA2‐2]
    1. Baker A, Richmond R, Lewin TJ, Kay‐Lambkin F. Cigarette smoking and psychosis: naturalistic follow up 4 years after an intervention trial. Australian and New Zealand Journal of Psychiatry 2010;44(4):342‐50. [DOI: 10.3109/00048670903489841] - DOI - PubMed
    1. Lan TH, Chiu HJ, Wu BJ, Hung TH, Hu TM. Readiness to quit and smoking reduction outcomes. American Journal of Psychiatry 2007;164(5):827‐8. - PubMed
Barbarin 1978 {published data only}
    1. Barbarin OA. Comparison of symbolic and overt aversion in the self‐control of smoking. Journal of Consulting and Clinical Psychology 1978;46(6):1569‐71. - PubMed
Batra 2003 {published data only}
    1. Batra A, Haustein K‐O, Friederich HM, Zschatsch I. Controlled smoking reduction ‐ results of a placebo‐controlled smoking reduction study with nicotine chewing gum [Kontrollierte rauchreduktion ‐ ergebnisse aus einer placebo‐kontrollierten rauchreduktionsstudie mit Nikotinkaugummi]. Verhaltenstherapie 2003;13(S1):5.
Batra 2005 {published data only}
    1. Batra A, Klingler K, Landfeldt B, Friederich HM, Westin A, Danielsson T. Smoking reduction treatment with 4‐mg nicotine gum: a double‐blind, randomized, placebo‐controlled study. Clinical Pharmacology and Therapeutics 2005;78(6):689‐96. [DOI: 10.1016/j.clpt.2005.08.019] - DOI - PubMed
    1. Landfeldt B, Batra A, Friederich HM, Klingler K, Westin A. Smoking reduction with a 4 mg nicotine gum ‐ final results from a placebo‐controlled trial over 13 months. Society for Research on Nicotine and Tobacco 5th European Meeting; 2003 Nov 20‐22; Padua, Italy. 2003.
Beavers 1973 {published data only}
    1. Beavers ME. Smoking Control: a Comparison of Three Aversive Conditioning Treatments [thesis]. USA: Dissertation Abstracts International, 1973.
Becona 1991 {published data only}
    1. Becona E, Gomez‐Duran BJ. Reduction of cigarette intake at baseline and efficacy of a smoking cessation programme [Descenso del consumo de cigarrillos en la linea base y eficacia de un programa para dejar de fumar]. Revista Española de Drogodependencias 1991;16(4):277‐84.
Becona 1993 {published data only}
    1. Becona E, Garcia MP. Nicotine fading and smokeholding methods to smoking cessation. Psychological Reports 1993;73(3):779‐86. - PubMed
Becona 1998 {published data only}
    1. Becona E, Vazquez FL. Efficacy of a behavioral multicomponent cessation program at five year follow‐up. Research Communications in Biological Psychology & Psychiatry 1998;23(1‐2):9‐17.
Becona 2001 {published data only}
    1. Becona E, Vazquez FL. Comparison of the efficacy of a self‐help smoking cessation by mail with a manual in one‐time intervention or weekly intervention [Comparacion de la eficacia de un programa de autoayuda para dejar de fumar distriuido por correo en un manual en un unico envio o semanalmente en folletos]. Psiquis 2001;22(4):41‐50.
Becona Iglesias 1989 {published data only}
    1. Becona Iglesias E, Lista Rubianes MJ. Treatment of smokers with nicotine fading techniques. Psiquis Revista de Psiquiatria, Psicologia y Psicosomatica 1989;10(4):38‐44.
Berecz 1971 {published data only}
    1. Berecz JM. Reduction of smoking through self‐administered aversion conditioning of imagined behavior. Annual Convention of the American Psychological Association. 1971:429‐30.
Berecz 1984 {published data only}
    1. Berecz, JM. Superiority of a low‐contrast smoking cessation method. Addictive Behaviors 1984;9(3):273‐8. [DOI: ] - PubMed
Berger 2006 {published data only}
    1. Berger, J. Smoking reduction and lung cancer risk. JAMA 2006;295(9):1001‐2. - PubMed
Bernard 1972 {published data only}
    1. Bernard HS, Efran JS. Eliminating versus reducing smoking using pocket timers. Behaviour Research and Therapy 1972;10(4):399‐401. - PubMed
Blalock 2001 {published data only}
    1. Blalock JA, Cinciripini PM, Hogan MC. Transdermal nicotine and gradual reduction for smoking cessation. Society for Research on Nicotine and Tobacco 7th Annual Meeting, 2001 Mar 21‐23; Seattle, USA. 2001:74. [PO3 31]
Bloch 2010 {published data only}
    1. Bloch B, Reshef A, Cohen T, Tafla A, Gathas S, Israel S, et al. Preliminary effects of bupropion and the promoter region (HTTLPR) serotonin transporter (SLC6A4) polymorphism on smoking behavior in schizophrenia. Psychiatry Research 2010;175(1‐2):38‐42. [DOI: 10.1016/j.psychres.2008.12.015] - DOI - PubMed
Bolliger 2000b {published data only}
    1. Bolliger CT. Practical experiences in smoking reduction and cessation. Addiction 2000;95(S1):19‐24. - PubMed
Borland 1999 {published data only}
    1. Borland R, Owen N, Tooley G, Treijs I, Roberts L, Hill D. Promoting reduced smoking rates in the context of workplace smoking bans. American Journal of Health Promotion 1999;14(1):1‐3. [DOI: 10.4278/0890-1171-14.1.1] - DOI - PubMed
Borland 2013 {published data only}
    1. Borland R, Balmford J, Swift E. Effects of timing of initiation and planning on smoking cessation outcomes: study protocol for a randomised controlled trial. BMC Public Health 2013;13:235. [DOI: 10.1186/1471-2458-13-235] - DOI - PMC - PubMed
Bowers 1987 {published data only}
    1. Bowers TG, Winett RA, Frederiksen LW. Nicotine fading, behavioral contracting, and extended treatment: effects on smoking cessation. Addictive Behaviors 1987;12(2):181‐4. - PubMed
Bradford 1991 {published data only}
    1. Bradford TS. The Effects of Combining Behavioral Counselling with Nicotine Fading and Smoke Holding in Medically At‐Risk Adult Smokers [thesis]. USA: Dissertation Abstracts International, 1991.
Brown 1984 {published data only}
    1. Brown RA, Lichtenstein E, McIntyre KO, Harrington‐Kostur J. Effects of nicotine fading and relapse prevention on smoking cessation. Journal of Consulting and Clinical Psychology 1984;52(2):307‐8. [DOI: ] - PubMed
Brue 2001 {published data only}
    1. Brue V, Karlson K, Escamilla G. Utility of a computerized device in scheduled reduced smoking. Society for Research on Nicotine and Tobacco 7th Annual Meeting; 2001 Mar 21‐23; Seattle, USA. 2001:106. [PO2 78)]
Buceta 1989 {published data only}
    1. Buceta JM, Lopez A. Application of a behavioral‐cognitive intervention program for smoking cessation. Revista Intercontinental de Psicologia y Educacion 1989;2(3):81‐99.
Burling 1982 {published data only}
    1. Burling TA, Stitzer ML, Bigelow GE, Russ NW. Techniques used by smokers during contingency motivated smoking reduction. Addictive Behaviors 1982;7(4):397‐401. - PubMed
Burling 1989 {published data only}
    1. Burling TA, Marotta J, Gonzalez R, Moltzen JO, Eng AM, Schmidt GA, et al. Computerized smoking cessation program for the worksite: treatment outcome and feasibility. Journal of Consulting and Clinical Psychology 1989;57(5):619‐22. - PubMed
Burling 1994 {published data only}
    1. Burling TA, Seidner AL, Gaither DE. A computer‐directed program for smoking cessation treatment. Journal of Substance Abuse 1994;6(4):427‐31. - PubMed
Burris 2014 {published data only}
    1. Burris JL, Carpenter MJ, Wahlquist AE, Cummings MK, Gray KM. Brief, instructional smokeless tobacco use among cigarette smokers who do not intend to quit: a pilot randomized clinical trial. Nicotine & Tobacco Research 2014;16(4):397‐405. [DOI: ] - PMC - PubMed
Cacciapaglia 2007 {published data only}
    1. Cacciapaglia HM, Kaplar ME, McConnell K, Schwetschenau HM, Carels RA. A stepped‐care approach to smoking cessation and harm reduction. Annals of Behavioral Medicine 2007;33(S1):205.
Caponnetto 2013 {published data only}
    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. [DOI: 10.1371/journal.pone.0066317] - DOI - PMC - PubMed
    1. NCT01194583. Randomised controlled trial investigating the efficacy and safety of an electronic nicotine delivery device (e‐cigarette) without nicotine cartridges in smokers. clinicaltrials.gov/show/nct01194583 (first received 3 September 2010).
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 2014;15(1):88. [DOI: 10.1186/1745-6215-15-88] - DOI - PMC - PubMed
Cassidy 2018 {published data only}
    1. Cassidy RN, Jackson KM, Rohsenow DJ, Tidey JW, Tevyaw TO, Barnett NP, et al. Contingency management for college student smokers: the role of drinking as a moderator and mediator of smoking abstinence during treatment. Addictive Behaviors 2018;80:95‐101. [DOI: 10.1016/j.addbeh.2018.01.017] - DOI - PMC - PubMed
Chambliss 1979 {published data only}
    1. Chambliss C, Murray EJ. Cognitive procedures for smoking reduction: symptom attribution versus efficacy attribution. Cognitive Therapy and Research 1979;3(1):91‐5.
Chen 2013 {published data only}
    1. Chen HK, Lan TH, Wu BJ. A double‐blind randomized clinical trial of different doses of transdermal nicotine patch for smoking reduction and cessation in long‐term hospitalized schizophrenic patients. European Archives of Psychiatry and Clinical Neuroscience 2012;263(1):75‐82. [DOI: 10.1007/s00406-012-0338-3] - DOI - PubMed
Cinciripini 1994 {published data only}
    1. Cinciripini PM, Lapitsky LG, Wallfisch A, Mace R, Nezami E, Vunakis H. An evaluation of a multicomponent treatment program involving scheduled smoking and relapse prevention procedures: initial findings. Addictive Behaviors 1994;19(1):13‐22. - PubMed
Colby 2005 {published data only}
    1. Colby SM, Monti PM, O'Leary Tevyaw T, Barnett NP, Spirito A, Rohsenow DJ, et al. Brief motivational intervention for adolescent smokers in medical settings. Addictive Behaviors 2005;30(5):865‐74. - PubMed
Colletti 1978 {published data only}
    1. Colletti G. The Relative Efficacy of Participant Modeling, Participant Observer, and Self‐monitoring Procedures as Maintenance Strategies Following a Positive Behaviorally Based Treatment for Smoking Reduction [thesis]. USA: Dissertation Abstracts International, 1978.
Colletti 1979 {published data only}
    1. Colletti G, Stern L. Two‐year follow‐up of a nonaversive treatment for cigarette smoking. Journal of Consulting and Clinical Psychology 1980;48(2):292‐3. - PubMed
Colletti 1980 {published data only}
    1. Colletti G, Supnick JA. Continued therapist contact as a maintenance strategy for smoking reduction.. Journal of Consulting and Clinical Psychology 1980;48(5):665‐7. [DOI: ] - PubMed
Colletti 1982 {published data only}
    1. Colletti G, Supnick JA, Rizzo AA. Long‐term follow‐up (3‐4 years) of treatment for smoking reduction. Addictive Behaviors 1982;7(4):429‐33. - PubMed
Corty 1984 {published data only}
    1. Corty E, McFall RM. Response prevention in the treatment of cigarette smoking.. Addictive Behaviors 1984;9(4):405‐8. - PubMed
Cropsey 2008 {published data only}
    1. Cropsey KL, Jackson DO, Hale GJ, Carpenter MJ, Stitzer ML. Impact of self‐initiated pre‐quit smoking reduction on cessation rates: results of a clinical trial of smoking cessation among female prisoners. Addictive Behaviors 2011;36(1‐2):73‐8. - PMC - PubMed
Cropsey 2015 {published data only}
    1. Cropsey KL, Clark CB, Hendricks PS. Varenicline for smoking reduction prior to cessation. JAMA 2015;313(22):2284‐5. [DOI: ] - PubMed
Crosbie 1972 {published data only}
    1. Crosbie PV, Petroni FA, Stitt BG. The dynamics of "corrective" groups. Journal of Health and Social Behavior 1972;13(3):294‐302. [DOI: ] - PubMed
D'Ruiz 2017 {published data only}
    1. D'Ruiz CD, O'Connell G, Graff DW, Yan XS. Measurement of cardiovascular and pulmonary function endpoints and other physiological effects following partial or complete substitution of cigarettes with electronic cigarettes in adult smokers. Regulatory Toxicology and Pharmacology 2017;87:36‐53. [DOI: 10.1016/j.yrtph.2017.05.002] - DOI - PubMed
Darity 1997 {published data only}
    1. Darity WA, Chen TT, Tuthill RW, Buchanan DR, Winder AE, Stanek E, et al. A multi‐city community based smoking research intervention project in the African‐American population. International Quarterly of Community Health Education 1997;17(2):117‐30. [DOI: ] - PubMed
Daughton 1994 {published data only}
    1. Daughton DM, Millatmal T, Susman JL, Belenky S, Sitorius M, Floreani AA, et al. Abrupt abstinence is critical to smoking cessation success in a family practice setting. Journal of Smoking‐Related Disorders 1994;5(S1):319.
Delahunt 1977 {published data only}
    1. Delahunt JG. Effectiveness Assessment of Modified Treatments for the Elimination of Smoking [thesis]. USA: Dissertation Abstracts International, 1977.
Dlack 1999 {published data only}
    1. Dlack GW, Meador‐Woodruff JH. Nicotine replacement and smoking reduction in smokers with schizophrenia. Schizophrenia Research 1999;1‐3:276. - PubMed
Dogris 1998 {published data only}
    1. Dogris NJ. The Effect of a Prerecorded Hypnosis CD and Behavioral Fading on Smoking Cessation and Locus of Control [thesis]. USA: Dissertation Abstracts International, 1998.
Ebbert 2010 {published data only}
    1. Ebbert JO, Edmonds A, Luo X, Jensen J, Hatsukami DK. Smokeless tobacco reduction with the nicotine lozenge and behavioral intervention. Nicotine & Tobacco Research 2010;12(8):823‐7. [DOI: ] - PMC - PubMed
Ehrsam 1991 {published data only}
    1. Ehrsam RE, Buhler A, Muller P, Mauli D, Schumacher PM, Howald H, et al. Weaning of young smokers using a transdermal nicotine patch. Schweizerische Rundschau fur Medizin Praxis (Revue Suisse de Medecine Praxis) 1991;80(7):145‐50. - PubMed
Elliott 1978 {published data only}
    1. Elliott CH, Denney DR. A multiple component treatment approach to smoking reduction. Journal of Consulting and Clinical Psychology 1978;46(6):1330‐9. [DOI: ] - PubMed
Emmons 1988 {published data only}
    1. Emmons KM, Emont SL, Collins RL, Weidner G. Relapse prevention versus broad spectrum treatment for smoking cessation: a comparison of efficacy. Journal of Substance Abuse 1988;1(1):79‐89. - PubMed
Etringer 1984 {published data only}
    1. Etringer BD, Gregory VR, Lando HA. Influence of group cohesion on the behavioral treatment of smoking. Journal of Consulting and Clinical Psychology 1984;52(6):1080‐6. [DOI: ] - PubMed
Etter 2011 {published data only}
    1. Etter JF. Comparing abrupt and gradual smoking cessation: a randomized trial. Drug and Alcohol Dependence 2011;118(2‐3):360‐5. [DOI: 10.1016/j.drugalcdep.2011.04.016] - DOI - PubMed
Euler 1973 {published data only}
    1. Euler VHA. Reduction of cigarette smoking through self‐monitoring [Die reduktion des zigarettenrauchens durch selbst‐monitoring]. Zeitschrift fur Klinische Psychologie und Psychotherapie 1973;21(3):271‐82. - PubMed
Evins 2001 {published data only}
    1. Evins AE, Cather C, Rigotti NA, Freudenreich O, Henderson DC, Olm Shipman CM, et al. Two‐year follow‐up of a smoking cessation trial in patients with schizophrenia: increased rates of smoking cessation and reduction. Journal of Clinical Psychiatry 2004;65(3):307‐11. - PubMed
    1. Evins AE, Mays VK, Rigotti NA, Tisdale T, Cather C, Goff DC. A pilot trial of bupropion added to cognitive behavioral therapy for smoking cessation in schizophrenia. Nicotine & Tobacco Research 2001;3(4):397‐403. [DOI: 10.1080/14622200110073920] - DOI - PubMed
    1. Evins AE, Mays VK, Rigotti NA, Tisdale T, Daigle A, Goff DC. Reduction In tobacco use in schizophrenia with bupropion SR and Cognitive Behavioral Therapy. Society for Research on Nicotine and Tobacco 6th Annual Meeting; 2000 Feb 18‐20; Arlington, USA. 2000.
Evins 2007 {published data only}
    1. Evins AE, Cather C, Culhane M, Birnbaum AS, Horowitz J, Hsieh E, et al. A placebo‐controlled study of bupropion SR added to high dose nicotine replacement therapy for smoking cessation or reduction in schizophrenia. Society for Research on Nicotine and Tobacco 12th Annual Meeting; 2006 Feb 15‐18; Orlando, USA. 2006:101. [POS2‐104]
    1. Evins AE, Cather C, Culhane MA, Birnbaum A, Horowitz J, Hsieh E, et al. A 12‐week double‐blind, placebo‐controlled study of bupropion SR added to high‐dose dual nicotine replacement therapy for smoking cessation or reduction in schizophrenia. Journal of Clinical Psychopharmacology 2007;27(4):380‐6. [DOI: 10.1097/01.jcp.0b013e3180ca86fa] - DOI - PubMed
    1. NCT00307203. Safety and effectiveness of sustained release bupropion in treating individuals with schizophrenia who smoke. clinicaltrials.gov/show/NCT00307203 (first received 27 March 2006).
Fagerström 2002a {published data only}
    1. Fagerström K. Smoking reduction in the management of COPD. Monaldi Archives for Chest Disease (Archivio Monaldi per le malattie del torace) 2002;57(5‐6):281‐4. - PubMed
Farkas 2001 {published data only}
    1. Farkas AJ, Pierce JP, Zhu SH. Home smoking restrictions: a brief cessation intervention for callers to the California Smoker's Helpline who are not ready to quit. Society for Research on Nicotine and Tobacco 7th Annual Meeting; 2001 March 21‐23; Seattle, USA. 2001:109. [PO4 48]
Fatemi 2005 {published data only}
    1. Fatemi SH, Stary JM, Hatsukami DK, Murphy SE. A double‐blind placebo‐controlled cross over trial of bupropion in smoking reduction in schizophrenia. Schizophrenia Research 2005;76(2‐3):353‐6. [DOI: 10.1016/j.schres.2005.02.021] - DOI - PubMed
Fatemi 2013 {published data only}
    1. Fatemi SH, Yousefi MK, Kneeland RE, Liesch SB, Folsom TD, Thuras PD. Antismoking and potential antipsychotic effects of varenicline in subjects with schizophrenia or schizoaffective disorder: a double‐blind placebo and bupropion‐controlled study. Schizophrenia Research 2013;146(1‐3):376‐8. [DOI: ] - PubMed
Feryo 2009 {published data only}
    1. Feryo MR. Self‐Directed Smoking Cessation Program [thesis]. USA: Dissertation Abstracts International, 2009.
Filia 2010 {published data only}
    1. Filia S, Baker A, Richmond R, Kay‐Lambkin F, Castle D, Williams J, et al. Randomised controlled trial of a healthy lifestyles intervention to reduce cardiovascular disease (CVD) risk among smokers with psychosis: interim results. Australian and New Zealand Journal of Psychiatry 2010;44(S1):A31‐2. [DOI: ]
Forgays 1987 {published data only}
    1. Forgays DG. Flotation rest as a smoking intervention. Addictive Behaviors 1987;12(1):85‐90. [DOI: ] - PubMed
Foxx 1979 {published data only}
    1. Foxx RM, Brown RA. Nicotine fading and self‐monitoring for cigarette abstinence or controlled smoking. Journal of Applied Behavior Analysis 1979;12(1):111‐25. - PMC - PubMed
    1. Foxx RM, Brown RM, Katz I. Nicotine fading and self‐monitoring for cigarette abstinence or controlled smoking: a two and one‐half year follow‐up. Behavior Therapist 1981;4(2):21‐3.
Foxx 1983 {published data only}
    1. Foxx RM, Axelroth E. Nicotine fading, self‐monitoring and cigarette fading to produce cigarette abstinence or controlled smoking. Behaviour Research and Therapy 1983;21(1):17‐27. [DOI: ] - PubMed
Franklin 2009 {published data only}
    1. Franklin TR, Harper D, Kampman K, Kildea‐McCrea S, Jens W, Lynch KG, et al. The GABA B agonist baclofen reduces cigarette consumption in a preliminary double‐blind placebo‐controlled smoking reduction study. Drug and Alcohol Dependence 2009;103(1‐2):30‐6. [DOI: ] - PMC - PubMed
Frederiksen 1976 {published data only}
    1. Frederiksen LW, Peterson Gl. Controlled smoking: development and maintenance. Addictive Behaviors 1976;1:193‐6.
Fuhrer 1972 {published data only}
    1. Fuhrer RE. The Effects of Covert Sensitization with Relaxation Induction, Covert Sensitization Without Relaxation Induction, and Attention‐Placebo on the Reduction of Cigarette Smoking [thesis]. USA: Dissertation Abstracts International, 1972.
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NCT01982110 {published data only}
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NCT02354872 {published data only}
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