TABLE 2.

Summary Findings and Effect Size Estimates for Parental Competence Outcomes at 6 and 12 months Postpartum in a Randomized Controlled Trial of a Home-Visiting Intervention for Teen Mothers, for All Participants^a

Outcome	Adjusted Mean for Intervention Group (N=159)	Adjusted Mean for Control Group (N=163)	Adjusted Mean Difference	95% CI	Effect Sizeb	p
Parenting knowledge (possible scores, 0–30)
Baseline	13.04	12.65	0.39	−0.32, 1.10	0.12	0.28
12 months postpartum	15.43	14.08	1.35	0.65, 2.04	0.33	0.001
PLOC Scale, parental self-efficacy subscalec (possible scores, 10–50)
6 months postpartum	22.98	23.83	−0.85	−1.97, 0.28	−0.13	0.14
12 months postpartum	23.21	24.71	−1.51	−2.62, −0.39	−0.23	0.01
HOME scale (possible scores, 0–37)d
6 months postpartum	22.79	22.75	0.04	−1.02, 1.10	<0.01	0.94
12 months postpartum	25.92	25.41	0.51	−0.62, 1.63	0.08	0.38
Home safety measurese at 12 months postpartum
Home safety attitudes (possible scores, 8–40)	29.54	28.61	0.94	0.10, 1.78	0.19	0.03
Home safety practices (possible scores, 0–4)	1.56	1.30	0.26	−0.02, 0.54	0.16	0.07

^aAdjusted for covariates, which included study site, use of alcohol during index pregnancy, lifetime use of cigarettes, and baseline Center for Epidemiologic Studies Depression Scale score.

^bStandardized pairwise differences are defined as the average between treatment group difference in outcome scaled by the standard deviation of the outcome. Standardized differences represent treatment effect size estimates on the standard deviation scale of the outcome. Values of 0.2, 0.5, or 0.8 are generally regarded as small, medium, and large, respectively (39).

^cPLOC Scale=Parental Locus of Control Scale (17).

^dHOME=Home Observation for Measurement of the Environment (33). HOME scale scores exclude the acceptance subscale, which was omitted because of concerns about cultural and age appropriateness.

^eHome safety measures are from reference 40.