Summary of adherence by measure.

aUnannounced pill counts and MEMS were planned for all 1,147 participants. For 46 participants, however, MEMS data were not expected because of enrollment shortly prior to the data analysis cut-off date and the lack of a subsequent clinic visit for uploading MEMS data. MEMS data were not available for eight (0.7%) of 1,101 participants with expected MEMS data owing to factors such as missing visits, device malfunction, or device loss. Similarly, for 70 participants, enrollment was too close to the data analysis cut-off date to expect a UPC following initiation of pill counting. Attempts at UPC were not successful for 36 (3.3%) of the remaining 1,077 participants.Q, quarter; M, month.