Intent-to-treat analysis in the presence of off-treatment or missing data
Article first published online: 2 MAR 2010
Copyright © 2010 John Wiley & Sons, Ltd.
Volume 10, Issue 3, pages 191–195, May/June 2011
How to Cite
Keene, O. N. (2011), Intent-to-treat analysis in the presence of off-treatment or missing data. Pharmaceut. Statist., 10: 191–195. doi: 10.1002/pst.421
- Issue published online: 2 MAR 2010
- Article first published online: 2 MAR 2010
- missing data;
- per protocol;
Intent-to-treat (ITT) analysis is viewed as the analysis of a clinical trial that provides the least bias, but difficult issues can arise. Common analysis methods such as mixed-effects and proportional hazards models are usually labeled as ITT analysis, but in practice they can often be inconsistent with a strict interpretation of the ITT principle. In trials where effective medications are available to patients withdrawing from treatment, ITT analysis can mask important therapeutic effects of the intervention studied in the trial. Analysis of on-treatment data may be subject to bias, but can address efficacy objectives when combined with careful review of the pattern of withdrawals across treatments particularly for those patients withdrawing due to lack of efficacy and adverse events. Copyright © 2010 John Wiley & Sons, Ltd.