The timed 25-foot walk is a more sensitive outcome measure than the EDSS for PPMS trials: an analysis of the PROMISE clinical trial dataset.

Our investigation suggests that the T25FW may be a more useful primary outcome measure than the EDSS in PPMS trials, and that its use may shorten clinical trials. Our findings on the impact of CELs at baseline on disability outcomes inform the critical appraisal of clinical trials in PPMS.