Drug use and treatment success among gang and non-gang members in El Salvador: a prospective cohort study

Table 2 Changes in DAT outcomes by gang membership

	Past month any illegal substance use		Frequency of past month binge drinking		Past month crime		Past 6 mo. gang risk activity
	t	OR	t	r	t	OR	t	r
Intercept	1.65	2.99	5.83**	.81	2.60*	5.68	11.20**	.94
Inv. Mills	−2.32*	.37	−1.75+	-.07	−2.70**	.33	−2.91**	-.12
Gang Membership	3.20**	3.53	-.12	.00	3.11**	3.76	11.98**	.43
Time	−6.21**	.10	−5.56**	-.17	−6.55**	.07	−13.06**	-.37
Interaction	−1.11	.67	1.55	.05	−2.41*	.37	−6.77**	-.20
	χ²	ICC	χ²	ICC	χ²	ICC	χ²	ICC
Repeated Observation Variance	664.56*	.16	723.99**	.08	625.12	.09	1319.41**	.40
Center Variance	57.18**	.09	46.92**	.03	43.39**	.05	24.90	.01

** p < .01, * p < .05, + p < .10; N = 625; t-tests are based on 18 df for the intercept, 622 df for the inverse Mill’s ratio and the gang membership main effect, and 1068 df for time and the interaction; effect size r calculated using the formula reported in Cohen [26]: r = [ t² / ( t² + df ) ]^.5.

ISSN: 1747-597X