TABLE 4.

HLM Results for 3-Level Model Examining the Effect of SWPBIS on Prosocial Behaviors

Positive Behaviorsa	Coefficient	SE	t Ratio	P Value
Intercept
Intercept	5.1609	0.0376	137.32	<.001
School-level variables
Mobility	−0.0036	0.0033	−1.10	NS
Student/teacher ratio	0.0021	0.0105	0.20	NS
Faculty turnover	−0.0010	0.0037	−0.27	NS
Enrollment	−0.0303	0.0174	−1.74	NS
Student-level variables
Special education status	−0.3323	0.0343	−9.70	<.001
Ethnicity (black)	−0.2090	0.0335	−6.25	<.001
Grade cohort	0.0807	0.0541	1.49	NS
FARMS	−0.2069	0.0252	−8.21	<.001
Gender	−0.2609	0.0179	−14.57	<.001
Slope (growth)
Intercept	−0.0651	0.0166	−3.93	<.01
School-level variables
SWPBIS intervention	0.0335	0.0159	2.11	<.05
Mobility	−0.0006	0.0011	−0.59	NS
Student/teacher ratio	−0.0048	0.0030	−1.59	NS
Faculty turnover	−0.0029	0.0013	−2.19	<.05
Enrollment	0.0143	0.0055	2.59	<.05
Student-level variables
Special education status	−0.0079	0.0108	−0.73	NS
Ethnicity (black)	−0.0133	0.0082	−1.63	NS
Grade cohort	−0.0056	0.0210	−0.27	NS
FARMS	−0.0064	0.0081	−0.79	NS
Gender	−0.0200	0.0077	−2.61	<.05
Post hoc cross-level interactions
Grade cohort × SWPBIS	0.0846	0.0306	2.77	<.01
Gender × SWPBIS	−0.0109	0.0132	−0.83	NS
Special education status × SWPIS	−0.0004	0.0161	−0.02	NS
Random Effect	Variance Component	χ2		P Value
Level 1	0.5328
Level 2	0.3877	36099.8		<.001
Level 3 time/slope	0.0029	401.3		<.001

Akaike information criterion = 94385.8; Bayesian information criterion = 94323.4. SWPBIS was coded 1 (intervention), 0 (comparison). FARMS indicates free or reduced-price meals status. Gender was coded 1 (male), 0 (female). Ethnicity was coded 1(black), 0 (all others). Grade cohort indicates the grade the youth was in when the trial began, coded 1 (kindergarten), 0 (grades 1 or 2).

^aResults presented are from the model that did not include the post hoc interactions. The interclass correlation for prosocial behavior was 0.05.