Outcome switching in clinical trials is a serious problem. Between October 2015 and January 2016, the COMPare team systematically checked every trial published in the top five medical journals, to see if they misreported their findings:
- We compared each clinical trial report with its protocol or registry entry. Some trials reported their outcomes perfectly. For the others, we counted how many of the outcomes pre-specified in the protocol or registry were never reported. We also counted how many new outcomes were silently added.
- When we detected unreported or added outcomes, we wrote a letter to the journal pointing them out. We tracked which journals published our letters – and which did not.
Here’s what we found.
On average, each trial reported just loading…% of its specified outcomes. And on average, each trial silently added loading… new outcomes.