Disadvantaged children often face higher risk of developing emotional and behavioral difficulties than their affluent peers. Substantial research has suggested that preschool is an effective setting for preventive interventions to reduce children's behavior problems, especially for economically disadvantaged children. The Chicago School Readiness Project (CSRP), a classroom-based randomized controlled trial in Head Start settings, provided multifaceted services to support teachers’ classroom management and to reduce children's risk of elevated behavior problems. The interventions included a total of 30 hours of teacher training on behavior management strategies from September to March in the Head Start year, the placement of mental health consultants in classrooms once per week to coach teachers in implementing the behavior management strategies, and individual mental health consultation services for a small number of children (3-4 children per class) with high emotional and behavioral problems. The CSRP included a total of 602 children in 35 classrooms from 18 Head Start sites.

In this study we investigate both the short- and long-term effects of the CSRP on children's behavior problems reported by parents. We first examine whether the CSRP interventions can reduce children's behavior problems in kindergarten as well as in third and fifth grades. We use hierarchical linear modeling (HLM) to account for the multilevel structure of the CSRP data, in which children were nested within classrooms and classrooms were nested within Head Start sites. We further conduct growth curve modeling to assess the initial status as well as individual change over time and between individual differences in patterns of growth from Head Start to fifth grade using the repeated measures of behavior problems. We also examine whether the CSRP effects are moderated by child gender, race/ethnicity, family poverty-related risks (i.e., mother having less than high school education, mother working 10 hours or less per week, and family income-to-needs ratio at less than 50% of federal poverty threshold), and initial behavioral skills at baseline.

Children's behavior problems are measured by the Behavior Problems Index (BPI) from parents' reports. We focus on the two domains of BPI (i.e., Internalizing and Externalizing Behavior Problems) and further use the six subscales of BPI, including antisocial behaviors, anxious/depressed mood, headstrong behaviors, hyperactive behaviors, immature dependency, and peer conflict/social withdrawal. The covariates in the analyses include child, mother, and family characteristics as well as teacher and classroom covariates at baseline. Since the CSRP random assignment was conducted at the Head Start site level using a pairwise procedure, we also control for site-pair fixed effects. Based on developmental theories and prior empirical research, we expect that the CSRP interventions can reduce parent-reported behavior problems of children after Head Start and can also affect the growth rate in children’s behavior problems.

The study may provide new evidence on the long-term effects of classroom-based early interventions on low-income children's behavior problems. The findings can provide important implications for policymakers and help them make decisions on allocating scarce public funds to preventive interventions that target economically disadvantaged children who face multiple family and developmental risks.