A GLMM analysis with an autoregressive heterogeneous covariance structure best fit the data and showed a significant difference between treatment conditions, F(1, 941) = 5.35, p = .02, but not an effect for week (p = .49) or an interaction of treatment and week (p = .91). The odds ratio for ACT participants not using during a given week was 2.32 (95% CI [1.14, 4.74]), showing that they were more than 21¼ times more likely to not use substances during any week than participants in TAU were.
