Table 5.

Summary of GEE Model Predicting Drinking from Age and Hangover Severity

	Dependent Measures
	Likelihood of Drinking a			Volume of Alcohol Use b
Predictor	Exp(B)	95% CI	p	β	95% CI	p
Age	2.569	[1.804, 3.658]	< .001	0.001	[−0.110, 0.111]	.993
Sex	1.041	[0.849,1.278]	.698	0.188	[0.083, 0.294]	< .001
Between-person hangover severity	1.050	[0.906, 1.217]	.519	0.180	[0.088, 0.272]	< .001
Within-person hangover severity	0.894	[0.724, 1.103]	.294	−0.055	[−0.122, 0.013]	.111
Age × Sex	1.023	[0.741, 1.411]	.891	−0.002	[−0.110, 0.106]	.975
Age × Within-person hangover severity	0.817	[0.576, 1.160]	.258	0.028	[−0.051, 0.106]	.490
Sex × Within-person hangover severity	1.082	[0.946, 1.236]	.250	0.037	[−0.025, 0.099]	.246

Note. Continuous measures are standardized. Sex was coded −1 for females and 1 for males. The reported coefficients represent standardized effects (effect size d). Between-subject hangover severity = grand-mean centered average hangover severity during the monitoring period and reflects the between-person effect; Within-person hangover severity = person-centered hangover severity during the monitoring period and reflects the within-person effect. The pattern of significant results remained unchanged when the data source (i.e., sample) and person-level covariates (i.e., alcohol dependence, baseline drinking levels, and weight) were included in the model. Thus, we report the results of the model without these additional covariates to preserve statistical power. GEE = generalized estimating equation; CI = confidence interval;

^aBinary outcome (0 when participants abstained versus 1 when participants reported any alcohol use).

^bContinuous outcome (# of standard drinks consumed each drinking day). The three-way interactive effect of age, sex, and within-person prior day drinking volume was not significant, and exclusion of all main and interactive effects of sex also did not alter our pattern of significant results.