Table 2.

Cox Proportional Hazards Models Predicting Dropout from Cannabis Use and non-Adherence to Medication, Controlling for Medication, Site, Race, Sex, Age, and SES

	Dropout		Non-Adherence
	Hazard Ratio	95% CI	Hazard Ratio	95% CI
Cannabis Use	6.4*	[1.2, 35.6]	2.4***	[1.5, 3.9]
Medication (1=Olanazapine, 2=Risperidone)	1.3	[0.3, 4.6]	1.1	[0.7, 1.7]
Site (0 = Hillside, 1 = Bronx)	1.7	[0.4, 8.0]	5.4***	[3.3, 8.9]
Sex (1 = male, 2 = female)	3.4	[0.8, 14.4]	0.6	[0.3, 1.2]
Age	1.0	[0.9, 1.2]	1.0	[1.0, 1.1]
Socioeconomic Status	0.9	[0.9, 1.0]	1.0	[1.0, 1.0]
Black	1.2	[0.1, 12.2]	1.2	[0.5, 2.8]
Latino	7.9	[0.6, 104.2]	0.5	[0.2, 1.6]
Race: (ref = white)
Asian	4.7	[0.4, 57.9]	†
Other	2.0	[0.1, 37.6]	2.4+	[0.9, 6.1]
Model Fit χ2	18.9*		92.1***
# Participants	103		96
# “Failure” Events	12		90
Months at risk	986		927
Results illustrated in	Figure 1		Figure 2

Note: Cannabis Use is a time-varying covariate; all other predictors are time-invariant.

⁺p < .10

^*p < .05

^**p < .01

^***p < .001.

^†Asians had to be excluded from this analysis because there were no months during which an Asian participant both had valid data for cannabis use and was observed to be non-adherent.