Intervention Found To Raise I.Q. of Low-Birthweight Babies
Deborah L. Cohen
A national early-intervention project for low-birthweight babies succeeded in raising the I.Q.'s and verbal skills of some of the children, a new study reports.
The study, reported in the Oct. 26 issue of the Journal of the American Medical Association, tracked 985 low-birthweight babies, 377 of whom received home visits and care at special centers from birth to age 3.
The study found that, by age 5, the heaviest of the babies who received special services had higher I.Q.'s and verbal skills than those who did not.
The project, known as the Infant Health and Development Program, involved researchers at eight institutions and is believed to be the largest multi-site study of its kind in the United States.
A new book by Charles Murray and the late Richard J. Herrnstein linking poverty and low intelligence has renewed debate over the degree to which social programs can raise the I.Q.'s of disadvantaged children.
Many educators have assailed the book's thesis that such programs are doomed to fail because of the large role heredity plays in determining intelligence. (See Education Week, Oct. 26, 1994.)
While the new study's positive effects were limited to the heaviest of the babies, its findings demonstrate that "early experience can influence how children are functioning when they get to the school door," said Jeanne Brooks-Gunn, a professor of child development at Columbia University's Teachers College and the study's lead author.
"These results are very promising in terms of the education of at-risk children," she said.
To qualify for the study, babies had to weigh no more than 2,500 grams, or about 5 pounds, 7 ounces. About two-thirds of those who received services weighed no more than 2,000 grams, or about 4 pounds, 6 ounces.
The children received regular home visits throughout the study and attended preschool in specially designed child-development centers in their second and third years.
Both lighter and heavier babies who received the special services outperformed the control group in verbal and cognitive skills at age 3 and had fewer behavior problems.
But the effects were sustained through age 5--two years after the intervention ended--only for the heavier group, who had I.Q. scores averaging 3.7 points higher and verbal scores 4.2 points higher than the control group's.
The study found no significant differences in behavior or health between children in the project and control groups at age 5.
But for the heavier group, Ms. Brooks-Gunn said, the "modest sustained effects in verbal ability parallel those found in normal-birthweight samples of poor children."
It is encouraging that the gains remained for two years after services ended, Ms. Brooks-Gunn said, because some studies have shown that the edge preschool programs give poor children when they start school fades quickly.
She acknowledged, however, that a wider range of assessments than I.Q. scores and more follow-up studies beyond age 5 are needed to gauge the program's effects on school performance.
The study, she said, also suggests that different or more intensive services might improve the outcomes of the lowest birthweight babies, who in recent years are surviving in greater numbers because of advances in medical care.
The study was funded by the Robert Wood Johnson Foundation, the Pew Charitable Trusts, the National Bureau of Maternal and Child Health and Resources Development, and the National Institute for Child Health and Human Development.