No abstract

For 4 decades, vigorous efforts have been based on the premise that early intervention for children of poverty and, more recently, for children with developmental disabilities can yield significant improvements in cognitive, academic, and social outcomes. The history of these efforts is briefly summarized and a conceptual framework presented to understand the design, research, and policy relevance of these early interventions. This framework, biosocial developmental contextualism, derives from social ecology, developmental systems theory, developmental epidemiology, and developmental neurobiology. This integrative perspective predicts that fragmented, weak efforts in early intervention are not likely to succeed, whereas intensive, high-quality, ecologically pervasive interventions can and do. Relevant evidence is summarized in 6 principles about efficacy of early intervention. The public policy challenge in early intervention is to contain costs by more precisely targeting early interventions to those who most need and benefit from these interventions. The empirical evidence on biobehavioral effects of early experience and early intervention has direct relevance to federal and state policy development and resource allocation.

Attempted to examine the generalizability of environment/development relationships among 3 ethnic groups across the first 3 years of life. Social status did not show a consistent relationship to either quality of home environment or children's developmental status across the various groups. Results indicated a fairly consistent relationship between HOME scores and children's developmental status, although there were some ethnic and social status differences in the relationship. Measures of specific aspects of the child's home environment, such as parental responsivity and availability of stimulating play materials, were more strongly related to child developmental status than global measures of environmental quality such as SES. When the child's early developmental status and early home environment were both very low, the likelihood of poor developmental outcomes was markedly increased compared with cases when only one was low.

In the Abecedarian Project, a prospective randomized trial, the effects of early educational intervention on patterns of cognitive and academic development among poor, minority children were examined. Participants in the follow-up were 104 of the original 111 participants in the study (98% African American). Early treatment was full-time, high-quality, educational child care from infancy to age 5. Cognitive test scores collected between the ages of 3 and 21 years and academic test scores from 8 to 21 years were analyzed. Treated children, on average, attained higher scores on both cognitive and academic tests, with moderate to large treatment effect sizes observed through age 21. Preschool cognitive gains accounted for a substantial portion of treatment differences in the development of reading and math skills. Intensive early childhood education can have long-lasting effects on cognitive and academic development.

Follow-up data, obtained 4-7 years after intervention ended, are presented for the Carolina Abecedarian Project, an experimental study of early childhood educational intervention for children from poverty families. Subjects were randomly assigned to 1 of 4 intervention conditions: educational treatment from infancy through 3 years in public school (up to age 8); preschool treatment only (infancy to age 5); primary school treatment only (age 5-8 years), or an untreated control group. Positive effects of preschool treatment on intellectual development and academic achievement were maintained through age 12. School-age treatment alone was less effective. Results generally supported an intensity hypothesis in that scores on cognitive and academic achievement measures increased as duration of treatment increased.