non-white), gender, and site. This study had a priori power = .88 to detect a clinically significant improvement in abstinence rates of 12% at 6-months post-treatment (e.g., 12 vs. 24%), with no correction for multiple comparisons (α = .05) and power = .60 for the Bonferroni-corrected α = .005. To detect an improvement in abstinence rates of 15% (e.g., 12 vs. 27%) this study had a priori power = .97 for α = .05 and power = .84 for α = .005.
