The FDA released its final guidance regarding the use of covariates to improve the precision of statistical analyses in clinical trials on 26 May 2023. It is a major step forward in the statistical analysis of clinical trial data. Recognizing that nearly a decade ago, the publication of the EMA guide initiated the movement, the FDA has crystallized the concept with the current guidance.
The baseline pain variability (BPV) has often been presented as positively correlating with the placebo response (PR) and associated with a lack of consistency in the subjects’ pain evaluation. Excluding high BPV subjects should then improve the precision of the treatment response. Another common method to increase the essay sensitivity is to adjust the analysis for covariates
Clinical trials data analyses can employ baseline covariates to control for factors that may impact measurement of outcomes – particularly to describe individual patient characteristics that may or may not relate to treatment response. For example, patient age may be used as a baseline covariate to reduce data variability resulting from this factor. The use of baseline