Table 11.

Summary of hierarchical regression analyses for variables predicting MDI and PDI scores

Variable	Ba	β	R2 Change	p
Criterion: MDI
Step 1: age at testing	−4.2	−.30	.00	<.002
Step 2: gestational age	−1.1	−.13	.02	<.09
Step 3: general severity index	−10.6	−.26	.04	<.03
Step 4: alcohol use	−7.3	−.20	.10	<.08
Step 5: cocaine use	−9.3	−.25	.05	<.05
Criterion: PDI
Step 1: age at testing	0.30	.02	—	.76
Step 2: gestational age	−0.46	.03	—	.73
Step 3: general severity index	−0.13	−.14	.04	.26
Step 4: alcohol use	0.4	.04	—	.69
Step 5: cocaine use	−8.4	−.27	.08	<.05

^aUnstandardized regression coefficient.