From December 2005 to May 2015, 1301 VIDUS and ACCESS participants who accessed MMT were included in the analyses. In total, the study sample consisted of 1301 participants who contributed 9809 observations, of which 121 (1.2%) observations did not include methadone dose and were removed from analysis, leaving a total of 9688 observations. The median number of follow-up assessments was 7 (Interquartile Range [IQR] = 2–12). Among the study sample, 288 (22.1%) participants ever discontinued MMT and 49 (3.8%) discontinued MMT more than once during the study period.
