It has been reported that significant variability in the ethics review process affects multisite studies. We analyzed 1,305 applications for multicenter studies (409 unique protocols), from 1st January 2020 to 20th September 2021. We examined the variability in the times to approval and the first observation and the variation in the level of risk assigned. The median [IQR] variabilities were 42.19 [15.23-82.36] days and 8.00 [3.12-16.68] days, for the times to approval and to the first observation, respectively. There was disagreement in the level of risk assigned by the Research Ethics Committee (REC) in 24.0% of cases. Independent predictors of variability included the number of REC members. In our study, we found substantial variability in the ethics review process among health research protocols. Also, we describe methods to readily measure the delays and the variations in the ethics review process.
Keywords: ethical approval; ethics review; institutional research boards; multicenter studies; research ethics committee; variability.