English to Russian Medical Medical: Pharmaceuticals studies of medications

обычно incidence перевожу как "заболеваемость, частота возникновения", в данном случае необходимо противопоставить 2 вида incidence в рамках одного и того же явления:

In fact, the subject incidence of each SRE component for first on-study SRE and the event incidence of each SRE component for first-and-subsequent on-study SRE were numerically lower in the XXX group compared with the XXX group in the integrated analysis.

(SRE - skeletal-related event)