Study 1
Brotman and colleagues (2008) conducted a randomized controlled trial that compares the intervention program to a no-treatment control condition. Ninety-two preschoolers (and parents) from the families of adolescents who had been adjudicated in family court in New York City participated in the study. Authors recruited participants, through youth records, who were younger than 16, had been adjudicated in two New York City boroughs between 1997 and 2001, and had preschool-aged siblings. The study authors defined a sibling as someone who is biologically related to the adjudicated youth or who lived with the adjudicated youth for at least a year, and who was also raised by the same caregiver. Families were eligible if siblings were between 33 months and 63 months, and the caregiver did not have a current substance abuse or psychotic disorder. Families in the intervention condition received 6 to 8 months of the prevention intervention and the 3-month booster. Families in the control condition received no intervention.
Ninety-two families agreed to participate in the trial. There were 47 families randomly assigned to the intervention condition, and 45 families randomly assigned to the control condition. Seven of the 92 families had more than one preschooler, so the child closest to 48 months was deemed the target child. Of the study sample, 68 percent of the 92 preschoolers were biological siblings (12 percent full; 56 percent half); 3 percent were adoptive siblings; and 28 percent were biological nieces, nephews, or cousins raised as siblings. Fifty-three percent of the preschoolers were girls, and 65 percent were African American, 27 percent were Latino/a, 1 percent were white, 1 percent were Asian, and 6 percent were mixed race/ethnicity. The average age of the children was 47.5 months, and 43 percent were not enrolled in a preschool or daycare program. Eighty-three percent of the caregivers were the biological mothers, 2 percent were the biological fathers, 10 percent were grandmothers, 3 percent were adoptive mothers, and 2 percent were other female relatives. The parents’ mean age was 36.3 years. Baseline comparison of the intervention and control groups did not produce any significant differences between the groups.
The primary outcome measured in the children was physical aggression, which was observed by blinded raters during the semistructured, parent-child interactions. Two parent-child interactions were measured, one at the home and one at the study center. At home, a 10-minute session was observed that included 5 minutes of child-directed free play and 5 minutes of a parent-directed puzzle task. At the study center, a 15-minute session was observed that included 7 minutes of child-directed free play, 5 minutes of a parent-directed puzzle task, and 3 minutes of clean up. The home assessments were coded at the time of the session, and the study center assessments were video recorded and coded at a later time. Different coders coded the home and study center sessions and were not involved in other aspects of the study. The Dyadic Parent-Child Interaction Coding System-Revised (DPICS-R) was used to assess aggressive behaviors, specifically using two codes: child physical negative and child destructive. The New York Parent Rating Scale (NYPRS-P) was filled out by parents to rate their children’s physical aggression. The scale, which was read aloud to parents, includes a five-item physical aggression scale. Parents were asked to rate their children’s behavior over the past 4 weeks.
Harsh parenting was measured by a composite of observations of parent-child interaction and parent report. The DPICS-R Critical Statements Scale and the Global Impressions of Parent-Child Interactions (GIPCI) Harsh Scale were used during observation of parent-child interaction, and two parent-report scales from the Parenting Practices Interview (PPI), the Harsh-C and Harsh-O scales, were used for the parent report. Responsive parenting was measured by observations of the parent-child interaction and coded using the DPICS-R Praise Scale and GIPCI Valence, Responsiveness, and Affection Scales.
Stimulation for learning was evaluated during the home visits with the Home Observation for the Measurement of the Environment-Early Childhood version (HOME-EC), in which raters used observation and interviews to determine the presence or absence of items. Three of the HOME subscales used were on learning, language, and academic stimulation. Stimulation for learning was only evaluated until time 3 (8 months), as the early childhood version of HOME is no longer age-appropriate at time 4 (16 months), and the elementary version differs significantly.
The effects of the intervention on children’s physical aggression and parenting practices were analyzed using the generalized estimating equation (GEE), which uses time-within-child as the unit of analysis with a regression model and accounts for the correlations of repeated measures. Follow-up measures were taken at 8 and 16 months after completion of the intervention. The study authors did not conduct subgroup analyses.