Table 3.

GEE test of model effects with smoking cessation as outcome variable and treatment group, race, and time as explanatory variables (N = 471)

Variable	Wald chi-square	df	p value
Intercept	3743.5	1	<.001
Treatment	3236.2	1	<.001
Race	2.1	1	.147
Time	33350.4	14	<.001
Treatment × time	5084.7	4	<.001
Treatment × race	4.8	1	.029

Note. GEE, generalized estimating equation; age, education, average cigarettes per day, change in smoking behavior since coming to prison, and prior mental health treatment were added as covariates.