The findings come from a longitudinal study on the effects of early child care supported by the National Institute of Child Health and Human Development (NICHD). They will be presented at the biennial meeting of the Society for Research in Child Development on April 4, 1997, at 4:30 p.m. at the Sheraton Washington Hotel in Washington, D.C.
"The most striking aspect of these results from the early child care study is that children are not being placed at a disadvantage in terms of cognitive development if they have high quality day care in their first three years," said NICHD's Director, Duane Alexander, M.D. "It's very important to study these issues as they are of such importance to American families."
A major way in which the NICHD Study of Early Child Care contributes to understanding the effects of child care is by moving beyond the global questions about whether child care is good or bad for children. Instead, it focuses on how the different aspects of child care, such as quantity and quality of care, are associated with children's cognitive and language development and mother-child interaction patterns over the first three years of life.
Just as important, the NICHD Study of Early Child Care examines effects of child care after taking into consideration other factors that shape children's development and their relationships with their mothers. These factors include family economic status, mother's psychological well being and intelligence, child sex and infant temperament. This study design makes it more likely that the effects discerned are truly due to child care, and not a function of other factors.
The study is clarifying the association between child care and children's cognitive development, as well as the association between child care and the mother-child relationship, two issues that are of deep concern to the over 50 million working mothers and their families in this country. Child care is becoming an ever increasing fact of life as more women stay in the work force after pregnancy and many more women are single parents. In 1980, according to U.S. census data, 38% of mothers, ages 18-44, with infants under one year of age, worked outside the home. By 1990, this percentage climbed to 50, a rate close to where it stands now. Most of these women return to work in their child's first three to five months.
Evidence is emerging from the study that across a wide range of child care settings, quality child care, as defined by positive caregiving and language stimulation given in the child care environment, are positively related to early cognitive and language development. While the quality of child care had a small but statistically significant relation to children's cognitive and linguistic outcomes, the combination of family income, maternal vocabulary, home environment, and maternal cognitive stimulation were stronger predictors of children's cognitive development.
"In this study, we found that the amount of language that is directed at the child in child care is an important component of quality provider-child interaction," said Dr. Sarah Friedman, NICHD coordinator of the study and one of its investigators. "This language input is predictive of children's acquisition of cognitive and language skills, which are the bedrock of school readiness."
Language stimulation was assessed by measuring how often caregivers spoke to children, asked them questions, and responded to their vocalizations. To assess children's cognitive development, researchers used standardized tests, including the Bayley Scales of Infant Development, the Bracken-Scale-of-Basic-Concepts school-readiness subtest, the MacArthur Communicative Development Inventory, and the Reynell Developmental Language Scale.
The small but consistent findings indicate that the higher the quality of child care in the first three years of life the greater the child's language abilities at 15, 24, and 36 months, the better the child's performance on the Bayley Scales of Infant Development at age two, and the more school readiness the child showed at age three.
Among children in care for more than 10 hours per week, those in center care, and to a lesser extent, those in child care homes, performed better on cognitive and language measures when the quality of the caregiver-child interaction was taken into account.
In addition to the cognitive findings, researchers also found that quality and amount of child care had a small but statistically significant association with the quality of the mother-child interaction. Again, a combination of other variables, including family environment, maternal education, and family income, were more influential in determining the quality of the mother-child interaction.
Researchers found that the amount of nonmaternal child care was weakly associated with less sensitive and engaged mother-child interactions. The more time infants and toddlers spent in non-maternal child-care arrangements, the less sensitive and positively involved were mothers with their infants at 6 months of age, the more negative they were with them at 15 months of age, the less positively affectionate the child was toward the mother at 24 and 36 months of age, and the less sensitive mothers were to their toddlers at the 36 month point.
Where effects of quality on mother-child interaction were found, higher quality of provider-child interaction in the child care setting predicted greater maternal involvement-sensitivity (at 15 and 36 months) and greater child positive engagement at 36 months.
Mother-child interaction was evaluated by videotaping mother and child together during play and observing mother's behavior toward the child to see how attentive, responsive, positively affectionate or restrictive the mother was when faced with multiple competing tasks (i.e., monitoring child, talking with interviewer).
In sum, what is happening at home and in families appears to be a powerful predictor of both cognitive outcomes and mother-child interaction. Still, with the family, maternal, and child care characteristics considered, the child care variables studied provided additional, significant prediction of children's cognitive and language outcomes and mother-child interaction.
In 1991, the NICHD Study of Early Child Care enrolled more than 1,300 families and their children from 10 locales throughout the country. The children, who were one month old or less at enrollment, their families, and their child-care arrangements are being followed through the child's seventh year of life. The families are diverse in terms of race, maternal education, family income, family structure (single-parent families are included), maternal employment status, type and quality of child care, and the number of hours that children spend in non-maternal care arrangements. Arrangements included father care, grandparent care, care by a non-relative in the child's home, child care homes, and center-based care.
The child care variables used in the analysis included information about the type of care, the amount of care, and the quality of care. Higher quality care was defined in terms of the interactions of child care providers with the study children. Interactions expected to promote positive affect, better social adjustment and greater cognitive and language skill were considered of higher quality.
Initiated and conducted by NICHD and investigators at 14 universities nationwide, the study was spurred by many questions from parents, developmental psychologists, and policy makers about the effects of early child care on children's development. Among the investigators' core interests have been how these child-care experiences affect children's cognitive and language development and the way in which parents relate to children who are in child care. These are important study foci because early cognitive and language development predicts future school achievement and performance on intelligence tests and because patterns of mother-child interaction predict future social, emotional, and cognitive development.
Last April, study investigators released data which evaluated the infants up to the 15 month point. They found that child care, in and of itself, neither adversely affects, nor promotes, the security of children's attachment to their mothers at the 15 month age point, provided the children were already receiving relatively sensitive care from their mothers.
For more information about the study, contact NICHD's Public Information and Communications Branch at (301) 496-5133. The NICHD is part of the National Institutes of Health, the biomedical research arm of the Federal government. Since its inception in 1962, the Institute has become a world leader in promoting research on development before and after birth; maternal, child, and family health; reproductive biology and population issues; and medical rehabilitation.