Outcome pre-specification requires sufficient detail to guard against outcome switching in clinical trials: a case study.

ABSTRACT: BACKGROUND:Pre-specification of outcomes is an important tool to guard against outcome switching in clinical trials. However, if the outcome is not sufficiently clearly defined, then different definitions could be applied and analysed, with only the most favourable result reported. METHODS:In order to assess the impact that differing outcome definitions could have on treatment effect estimates, we re-analysed data from TRIGGER, a cluster randomised trial comparing two red blood cell transfusion strategies for patients with acute upper gastrointestinal bleeding. We varied several aspects of the definition of further bleeding: (1) the criteria for what constitutes a further bleeding episode; (2) how further bleeding is assessed; and (3) the time-point at which further bleeding is measured. R

SUBMITTER: Kahan BC 

PROVIDER: S-EPMC5932799 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature