A major study launched at the Frank Porter Graham Child Development Center at the University of North Carolina at Chapel Hill showed that high-quality early-intervention services dramatically improved the intellectual performance and behavioral competence of premature, low-birthweight infants by the time they reached age 3.
The Infant Health and Development Program, which is described in the March 1992 issue of Pediatrics, was conducted at eight sites and involved 985 children, 377 in an experimental group and 608 in a control group.
Assistant Editor Deborah L. Cohen discussed the study with the lead researcher, Craig T. Ramey, who is now a professor of psychology and pediatrics and the director of the Civitan International Research Center at the University of Alabama at Birmingham.
Q. What kinds of interventions did you use to test your hypothesis?
A. The interventions consisted of pediatric surveillance and follow-up, home visiting by experienced and specially trained professionals, and the child’s attendance beginning at age 1 at a specially created child-development center. That center was a full-day center and operated basically year-round. Children attended until 3 years of age and continued to have their families participate in home visits, and there was [also] a family-support group.
The idea was to really create the kind of family center that allowed the child to receive direct education from highly experienced and highly trained educators while families received information and support concerning their role as knowledgeable, informed, and concerned parents.
Home visits in the first year [were] once a week, and in the second and third years, once every other week.
Q. What were your major findings?
A. We were able to reduce the incidence of developmental delay and of behavior problems as reported by the mother. The overall finding [was] that the incidence of mental retardation was reduced by a factor of 2.7 [when compared with the control group].
We further found that there was a strong and direct relationship between the amount of participation in the program by children and families and how well the children did both intellectually and behaviorally. For the children and families [whose participation ranked in the top third], there was a reduction in the incidence of mental retardation by a factor of almost 9 [compared with the control group]. For families who fell in the middle level of participation, it was reduced by a factor of 3. For the lowest third of participants, there was scarcely a reduction in the incidence of mental retardation at all.
Q. What sets this study apart from other studies demonstrating the benefits of early intervention?
A. It was the largest study of its kind ever conducted in early intervention and the first multi-site, controlled trial to test any specific early-intervention strategy. Second, it used random assignment of families to an experimental or controlled condition, which allows quite a strong causal incidence to be made.
Q. The children whose families participated most had the greatest gains, but you’ve noted that participation varied widely. What factors were linked with higher participation?
A. We have not yet been able to determine what the variations were the result of, and are conducting systematic research to determine that. It is certainly troubling, but also just very perplexing, because we had the resources to go to great lengths to ensure families could participate [and] to overcome many of the factors that would likely preclude some from participating. It just makes the puzzle that much more complicated.
Participation was not related to the mothers’ level of education, to the health status of the child, to variations across the sites. It doesn’t appear that socioeconomic status or the child’s degree of low birthweight or the degree of prematurity was related to participation.
Q. Given that it will be difficult in the current economic climate to garner the funding needed to support such extensive interventions, what is the minimum level of interventions you would recommend?
A. For children who are considered to be seriously at risk, a minimum program would consist of an intensive home visit program by well-trained professionals and some level of attendance at a well-equipped, well-staffed and knowledgeable child-development center on a weekly basis. [Preferably,] at least three hours a day.
Q. A common concern about preschool interventions is that early gains tend to wash out over time. What can be done to ensure that these children sustain their gains?
A. Follow-up is continuing on these children, and we have just written an article from the “Abecedarian’’ study--the prototype for this study--to show that continuous, intensive intervention is the most crucial factor in high-risk children’s long-term developmental outcomes.
If [the children move into] a nonsupportive environment, I would not expect the gains to be maintained. But if ... the key figures in the children’s lives--the parents, the teachers--continue to provide a high-quality, individualized program, I would expect the initial gains to be maintained.
Q. What are the key implications of your study for policymakers?
A. We now have very strong and clear evidence that high-quality early intervention can make a difference in the development of young children. Second, these findings strongly suggest that the intensity and quality of programs will have a direct bearing on how effective they are.
We can [now] begin to move on and ask questions about how variations in early intervention might produce differing levels of outcomes; we can begin to fine tune and get involved in some cost-effectiveness comparisons, which is a much more sophisticated discussion than we’ve had for a long time.
