A threshold value for a clinically meaningful difference in the relative change of facial acne lesion counts (ALCs) used in noninferiority studies was determined. A database of 4,081 patients with moderate-severe facial acne from different projects was analyzed. Objective ALCs were measured at baseline and endpoint by investigators, and patients also scored subjective ALCs at the end of the study. This was used as an anchor to give an empirically validated threshold for the relative change in ALC. This was compared to the default threshold value for practitioners-half the standard deviation (SD) value for a change in health-related quality of life. The relative change in ALCs was a mean of 40% ...