Abstract
A multidisciplinary international cohort of 72 expert statisticians and researchers recently proposed lowering the p value threshold from 0.05 to 0.005 to mitigate distortion of trial results and decrease bias. We hereby explored how a change to the p value threshold may alter the statistical significance of primary endpoints in gastroenterology (GE) randomized control trials (RCTs). We analyzed RCTs published in the 20 highest ranked GE and medicine journals. For each trial, we extracted the p values for the corresponding primary endpoints. We retrieved 233 RCTs, of which 159 were included in the final analysis yielding 202 primary endpoints. Of these endpoints, 60% had a p value less than 0.05 and when a threshold of less than 0.005 was applied, approximately 50% retained significance. We endorse a lower p value threshold as an actionable, provisional measure for improving statistical inference in GE RCTs until more long-term solutions become available.
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