Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Jun 30;21(1):596.
doi: 10.1186/s13063-020-04441-9.

E-Freeze - a randomised controlled trial evaluating the clinical and cost effectiveness of a policy of freezing embryos followed by thawed frozen embryo transfer compared with a policy of fresh embryo transfer, in women undergoing in vitro fertilisation: a statistical analysis plan

Jennifer L Bell  1 , Pollyanna Hardy  2 , Melanie Greenland  3 , Edmund Juszczak  3 , Christina Cole  3 , Abha Maheshwari  4 , Siladitya Bhattacharya  5 , Louise Linsell  3
Affiliations

E-Freeze - a randomised controlled trial evaluating the clinical and cost effectiveness of a policy of freezing embryos followed by thawed frozen embryo transfer compared with a policy of fresh embryo transfer, in women undergoing in vitro fertilisation: a statistical analysis plan

Jennifer L Bell et al. Trials. .

Abstract

Background: The E-Freeze trial is a multi-centre randomised controlled trial of fresh versus frozen embryo transfer for women undergoing in vitro fertilisation. This paper describes the statistical analysis plan for the E-Freeze trial.

Methods and design: E-Freeze is a two-arm parallel-group, multi-centre, individually randomised controlled trial to determine if a policy of freezing embryos, followed by thawed frozen embryo transfer, results in a higher healthy baby rate when compared with the current policy of transferring fresh embryos. Couples undergoing their first, second or third cycle of in vitro fertilisation at fertility centres in the UK were randomised to either fresh or frozen embryo transfer. The primary outcome is a healthy baby, defined as a live singleton baby born at term with an appropriate weight for gestation. This paper describes the statistical analysis plan for the trial, including the analysis principles, definitions of outcomes, methods for primary analysis, pre-specified subgroup analysis and sensitivity analysis. This plan was finalised prior to completion of recruitment to the trial.

Trial registration: ISRCTN registry: ISRCTN61225414 . Registered on 29 December 2015.

Keywords: Assisted conception; Complier average causal effect; Elective freezing; Fertility; Fresh embryo transfer; Frozen thawed embryo transfer; IVF; OHSS; Randomised controlled trial; Receptivity; Statistical analysis plan.

PubMed Disclaimer

Conflict of interest statement

EJ was a member of the National Institute for Health Research (NIHR) Health Technology Assessment (HTA) Commissioning Board (November 2013 to July 2016) and subsequently the General Board (November 2016 to July 2017). Presently (from November 2019) EJ sits on the Funding Committee for the NIHR/NHS England partnership scheme. EJ also reports funding from NIHR for the trial and reports receipt of funding from NIHR, outside the submitted work. All other authors have no competing interests.

Figures

Fig. 1
Fig. 1
Data collection schedule
See this image and copyright information in PMC

References

    1. Gamble C, Krishan A, Stocken D, et al. Guidelines for the content of statistical analysis plans in clinical trials. JAMA. 2017;318(23):2337–2343. doi: 10.1001/jama.2017.18556. - DOI - PubMed
    1. Maheshwari A, Bhattacharya S, Bowler U, et al. Study protocol: E-freeze - freezing of embryos in assisted conception: a randomised controlled trial evaluating the clinical and cost effectiveness of a policy of freezing embryos followed by thawed frozen embryo transfer compared with a policy of fresh embryo transfer, in women undergoing in vitro fertilisation. Reprod Health. 2019;16:81. doi: 10.1186/s12978-019-0737-2. - DOI - PMC - PubMed
    1. Royal College of Obstetrics and Gynaecology. Ovarian hyperstimulation syndrome, management (Green-Top Guideline No. 5). Available from: https://www.rcog.org.uk/en/guidelines-research-services/guidelines/gtg5/. Accessed 24 Aug 2015.
    1. Human Fertilization and Embryology Authority. Fertility treatment 2012 - trends & figures. Available from: http://www.hfea.gov.uk/docs/FertilityTreatment2012TrendsFigures.PDF. Accessed 24 Aug 2015.
    1. Pandey S, Shetty A, Hamilton M, Bhattacharya S, Maheshwari A. Obstetric and perinatal outcomes in singleton pregnancies resulting from IVF/ICSI: a systematic review and meta-analysis. Hum Reprod Update. 2012;18(5):485–503. doi: 10.1093/humupd/dms018. - DOI - PubMed

Publication types

MeSH terms