TABLE 3.

Three-Level Hierarchical Linear Model Estimated Slopes of Change per Log-Week

	Slope Estimates
	GC(SE);	IPT-AST (SE)	P Value	Cohen’s d [95% CI]
CES-D
Overall Slope  (Baseline,  24 Month)	−.18 (.04)	−.15 (.04)	.57	.08 [−.28, .30]
Short-Term Slope  (Baseline,  6 Month)	−.12 (.04)	−.23 (.04)	.02	.35 [.06, .63]
Follow-Up Slope  (6 Month–  24 Month)	−.41 (.15)	.13 (.14)	.01	.41 [.12, .70]
CGAS
Overall Slope  (Baseline,  24 Month)	1.26 (.19)	1.13 (.17)	.58	.08 [−28, .30]
Short-Term Slope  (Baseline,  6 Month)	1.74 (.17)	2.20 (.17)	.04	.31 [.02, .60]
Follow-Up Slope  (6 Month–  24 Month)	−.45 (.77)	−2.73 (.76)	.02	.33 [.04, .62]

Note: Slopes are model-based estimates within the three-level piecewise hierarchical linear model with two phases of change (baseline through 6-month follow-up and 6-month follow-up through 24-month follow-up). In these models, we employed a natural logarithmic transformation of time. Thus, slope estimates indicate expected rate of change in outcome per log-week, adjusted for covariates. Slope estimates for the CES-D are based on the square root transformed outcome. Estimates are derived from the full longitudinal model whereas the results reported by Young et al. (2016) used only data from baseline through the 6-month follow-up. Overall slope is the average of the short-term and follow-up slopes weighted by elapsed log-time per phase. Average elapsed time on the log-week scale was 3.75 for the short-term follow-up period (baseline through 6 months) and 1.04 for the long-term follow-up period (6 through 24 months). GC = group counseling; IPT-AST = Interpersonal Psychotherapy–Adolescent Skills Training; CES-D = Center for Epidemiologic Studies–Depression Scale; CGAS = Children’s Global Assessment Scale.