Strategy for intention to treat analysis in randomised trials with missing outcome data

Ian R White, Nicholas J Horton, James Carpenter, Stuart J Pocock, Ian R White, Nicholas J Horton, James Carpenter, Stuart J Pocock

Abstract

Loss to follow-up is often hard to avoid in randomised trials. This article suggests a framework for intention to treat analysis that depends on making plausible assumptions about the missing data and including all participants in sensitivity analyses

Conflict of interest statement

Competing interests All authors have completed the unified competing interest form at www.icmje.org/coi_disclosure.pdf (available on request from the corresponding author) and declare no support from any organisation for the submitted work; JC has undertaken paid consultancy for various drug companies; and no other relationships or activities that could appear to have influenced the submitted work.

Figures

https://www.ncbi.nlm.nih.gov/pmc/articles/instance/4788306/bin/whii799700.f1_default.jpg
Fig 1 Possible ways to impute outcome measures at visit 9 for a hypothetical participant in the obesity trial who drops out after visit 4: main analysis (last value brought forward) and three sensitivity analyses (1 assumes participants lost to follow-up return to baseline weight; 2 assumes 50% of weight regained, and 3 assumes intervention group regains a greater proportion of weight than controls)

References

    1. Moher D, Hopewell S, Schulz KF, Montori V, Gotzsche PC, Devereaux PJ, et al. CONSORT 2010 explanation and elaboration: updated guidelines for reporting parallel group randomised trials. BMJ 2010;340:c689.
    1. Peduzzi P, Wittes J, Detre K. Analysis as randomised and the problem of non-adherence: an example from the Veterans Affairs randomized trial of coronary artery bypass surgery. Stat Med 1993;12:1185-95.
    1. Altman D. Missing outcomes in randomized trials: addressing the dilemma. Open Med 2009;3(2):e51.
    1. Committee for Proprietary Medicinal Products. Points to consider on missing data. 2001. .
    1. Doody R, Gavrilova S, Sano M, Thomas R, Aisen P, Bachurin S, et al. Effect of dimebon on cognition, activities of daily living, behaviour, and global function in patients with mild-to-moderate Alzheimer’s disease: a randomised, double-blind, placebo-controlled study. Lancet 2008;372:207-15.
    1. Mackinnon A. Statistical treatment of withdrawal in trials of anti-dementia drugs. Lancet 2008;372:1382-3.
    1. Doody R, Seely L, Thomas R, Sano M, Aisen P. Authors’ reply. Lancet 2008;372:1383.
    1. Sterne JAC, White IR, Carlin JB, Spratt M, Royston P, Kenward MG, et al. Multiple imputation for missing data in epidemiological and clinical research: potential and pitfalls. BMJ 2009;338:b2393.
    1. Carpenter JR, Kenward MG. Missing data in clinical trials — a practical guide. Birmingham: National Institute for Health Research, 2008. .
    1. National Research Council. The prevention and treatment of missing data in clinical trials. 2010. .
    1. Kenward MG, Goetghebeur EJT, Molenberghs G. Sensitivity analysis for incomplete categorical tables. Stat Model 2001;50:15-29.
    1. Hollis S. A graphical sensitivity analysis for clinical trials with non-ignorable missing binary outcome. Stat Med 2002;21:3823-34.
    1. Astrup A, Rössner S, Van Gaal L, Rissanen A, Niskanen L, Al Hakim M, et al. Effects of liraglutide in the treatment of obesity: a randomised, double-blind, placebo-controlled study. Lancet 2009;374:1606-16.
    1. Ware JH. Interpreting incomplete data in studies of diet and weight loss. N Engl J Med 2003;348:2136-7.
    1. White IR, Carpenter J, Evans S, Schroter S. Eliciting and using expert opinions about non-response bias in randomised controlled trials. Clin Trials 2007;4:125-39.
    1. Shih WJ. Problems in dealing with missing data and informative censoring in clinical trials. Curr Contr Trials Cardiovasc Med 2002;3:4.
    1. European Medicines Agency. Guideline on missing data in confirmatory clinical trials. 2010. .
    1. Siddiqui O, Hung HM, O’Neill R. MMRM vs. LOCF: a comprehensive comparison based on simulation study and 25 NDA datasets. J Biopharm Stat 2009;19:227-46.
    1. Wittes J. Missing inaction: preventing missing outcome data in randomized clinical trials. J Biopharm Stat 2009;19:957-68.

Source: PubMed

3
Iratkozz fel