Outcomes
The primary outcome was 3-month (90th-day) milligram methadone dose. Secondary outcome measures included treatment retention, self-reported drug use, opioid withdrawal, craving, quality of life, and sleep. Outcomes were assessed in person via facilitated self-report at all 5 time points, except sleep (measured only at baseline and 1 and 3 months postbaseline).Three-month retention was assessed as a binomial variable (in treatment at day 90, yes or no). For descriptive purposes, retention was also counted as the number of days retained in treatment, from intake to day 90. We adopted the clinic’s definition of dropout (30 continuous absent days), with the last clinic visit considered the final day in treatment.Drug use was assessed via self-report of past 2-week use of 4 common substances: opioids (including heroin, fentanyl, nonprescribed opioids), cocaine, benzodiazepines, and alcohol; other was a fifth category. Total days used (out of 14) was recorded.Withdrawal was assessed using the objective (range, 0-13) and subjective Opiate Withdrawal Scales. Scores range from 0 to 64, with higher scores on these scales indicating greater withdrawal symptom severity.A craving assessment adapted from previous studiesQuality of life was assessed using the Abbreviated World Health Organization Quality of Life assessment. Scores range from 0 to 100, with higher scores indicating higher quality of life).Sleep was measured using the Pittsburgh Sleep Quality Index (PSQI. Scores range from 0 to 21, with higher scores indicating worse quality of sleep.