Clinical trials: what a waste - Trials that are unregistered, unfinished, unpublished, unreachable, or simply irrelevant

摘要

The utility of randomized controlled trials are contingent on how they are used. Chapman and colleagues show this in a sample of 3 95 trials relevant to surgical practice that were registered in Clincial-Trials.gov between 2008 and 2009. By the end of 2013,21% were discontinued, 34% of those that were completed were not published, and for 77% of the trials that had uncertain fate no way existed to reach investigators to find what had happened to them. This work adds to several other empirical evaluations showing that evidence from randomized controlled trials is wasted at multiple stages from conception to publication and beyond.Many trials are entirely lost, as they are not even registered. Substantial diversity probably exists across specialties, countries, and settings. Overall, in a survey conducted in 2012, only 30% of journal editors requested or encouraged trial registration.