Data Reduction
EMA
Of the 320 participants who met the baseline compliance eligibility criteria and attended the first treatment visit, 60 participated in an optional substudy that varied the frequency and amount of reinforcement for completing EMA (data to be presented in a separate report), and 3 participants were removed from the sample due to software problems with the mobile EMA app (data loss from a server crash), leaving a sample size of 257. Race, employment status, household income, and education were dichotomized as in the primary outcome paper of the parent trial [Within-subject percent compliance was computed for each of the 9 weeks, separately for morning assessments (up to 7 observations per week on each participant) and random assessments (up to 28 observations per week on each participant). Thirty (12%) participants dropped out of the study (withdrew or withdrawn or missed 3 visits in a row) during the EMA period. These participants were retained in the final sample, with data after their final week of study participation set to missing (not 0), and study dropout status (dropped out or completed) was examined as a predictor of EMA compliance rates.