Table 2.

Parameter estimates for multi-level model of change in estimated blood alcohol concentration (eBAC) over time by presence (vs. absence) of peers.

	Est.	95% CI	t
	Intercept	.033	[.017, .050]	3.93***
Presence of peers	−.011	[−.023, .0002]	−1.93
Slope-60	.027	[.013, .041]	3.81***
Slope-300	−.028	[−.047, −.010]	−3.04**
Peers x slope-60	.025	[.009, .042]	3.01**
Peers x slope-300	−.024	[−.046, −.002]	−2.15*
Study Day	.001	[−.001, .002]	0.73
Weekday (Sat. is reference)
Sunday	−.010	[−.024, .003]	−1.51
Monday	−.010	[−.024, .005]	−1.28
Tuesday	−.024	[−.040, −.009]	−3.07**
Wednesday	−.020	[−.035, −.006]	−2.75**
Thursday	−.015	[−.029, .000]	−1.98*
Friday	−.016	[−.027, −.005]	−2.76**
Hour of day	.000	[−.001, .000]	−1.54
Age	−.003	[−.006, −.001]	−2.53*
Report number	−.006	[−.017, .005]	−1.06

Note. N = 75 individuals, 789 observations used. Degrees of freedom were calculated using the Kenward-Roger approximation. Covariates in the model consisted of age (centered), whether participants made only 3 begin-/end-drink report pairs vs. unlimited drink reports (report number), day of study, weekday, and hour of day.

^*p < .05.

^**p < .01.

^***p < .001.