Table 2.

Piecewise Trajectories of Past 2-Week 10+ High-Intensity and 5+ Binge Drinking among U.S. Young Adults: Unconditional Growth Models Grouped by Gender and College Attendance

	N	Mean estimates (unstandardized):
		I (Age 18)		S1 (Age 18–21/22)		S2 (Age 21/22–25/26)
		Est	p	Est	p	Est	p
		10+ High-intensity drinking
Two-group model: gendera
Females	2,153	0.089	<.001	0.022	0.014	−0.026	0.001
Males	1,563	0.266	<.001	0.068	<.001	−0.026	0.001
Two-group model: college attendance b
Non-attendingc	1,593	0.171	<.001	0.016	0.254	0.002	0.871
Attending	1,434	0.134	<.001	0.088	<.001	−0.075	<.001
Four-group model: gender and college attendanced
Not attending - Females	910	0.083	<.001	0.010	0.389	0.007	0.578
Not attending - Males	683	0.279	<.001	0.010	0.389	0.007	0.578
Attending - Females	896	0.042	<.001	0.069	<.001	−0.058	<.001
Attending - Males	538	0.283	<.001	0.069	<.001	−0.058	<.001
	5+ Binge drinking
Two-group model: gendere
Females	2,146	0.275	<.001	0.105	<.001	−0.035	0.015
Males	1,554	0.509	<.001	0.207	<.001	−0.035	0.015
Two-group model: college attendancef
Non-attending	1,589	0.401	<.001	0.080	<.001	0.006	0.802
Attending	1,427	0.308	<.001	0.254	<.001	−0.092	<.001
Four-group model: gender and college attendanceg
Not attending - Females	907	0.296	<.001	0.040	0.084	<.001	0.987
Not attending - Males	682	0.497	<.001	0.142	<.001	<.001	0.987
Attending - Females	893	0.202	<.001	0.213	<.001	−0.091	<.001
Attending - Males	534	0.443	<.001	0.323	<.001	−0.091	<.001

Notes: I = Intercept; S1 = Slope 1; S2 = Slope 2. Decisions to free or constrain estimates to be equal across groups based on results of Satorra-Bentler scaled chi-square difference tests. For 10+ and 5+ gender grouping models, Slope 2 mean and variance were constrained to be equal across gender. For 10+ and 5+ college status grouping models, Slope 2 variance was constrained to be equal across college status. For the four-group gender and college status models, Slope 1 and Slope 2 means were constrained to be equal across gender within college status groups for 10+; Slope 2 mean was constrained to be equal across gender within college status groups for 5+.

^aχ²(df)=8.454(12); RMSEA=<.001; CFI=1.000; TLI=1.026.

^bχ²(df)=12.063(10); RMSEA=0.012; CFI=0.992; TLI=0.984.

^cAttending = Full-time student at 4-year college at age 19/20.

^dχ²(df)=32.264(30); RMSEA=0.010; CFI=0.991; TLI=0.988.

^eχ²(df)=20.926(14); RMSEA=0.016; CFI=0.989; TLI=0.985.

^fχ²(df)=26.255(11); RMSEA=0.030; CFI=0.977; TLI=0.959.

^gχ²(df)=44.440(28); RMSEA=0.028; CFI=0.975; TLI=0.964.