Study Links Increased Time in Child Care with Behavioral Problems

April 2001

The largest long term-study of child care in the U.S. has found that, when they are four-and-a-half years of age, and later, when they are in kindergarten, children who spent more time in child care during the first four-and-a-half years of life were rated as having more behavior problems than did children of the same age who spent less time in child care.

Child care was defined as regular care by anyone other than the mother that was routinely scheduled for at least 10 hours per week. The researchers noted that, between three- and 54-months of life, children were in non-maternal care an average of 26 hours per week. The upper limit for hours in non-maternal care was 76 hours per week. The ratings of problem behaviors, however, were mostly within the normal range. In general, the relation between time in child care and ratings of behavior problems was small-to-moderate.

The researchers, who are conducting the NICHD Study of Early Child Care, will present these findings at a meeting of the Society for Research in Child Development on April 19, at 2:30 p.m., at the Convention Center in Minneapolis, Minnesota.

The NICHD Study of Early Child Care enrolled just over 1,300 children at birth at 10 research sites throughout the United States. To date, the researchers have followed the children through infancy, toddlerhood, and the preschool years. Children participating in the on-going study were placed in a variety of child care arrangements, ranging from the most informal (care with relatives), to the most formal (center care). Periodically, researchers associated with the study provide updates on the children's progress as they proceed through the childhood years.

Results from the paper on the quantity of child care and children's social development show that:

• Children who spent more time in child care were rated as more aggressive toward other children and disobedient and/or defiant, not only when they were four-and-a-half, but also when they were in kindergarten.
• Children who spent more time in child care were rated as more fearful, shy and sad compared to children who spent less time in child care. These differences disappeared, however, by the time children were in kindergarten.
• The quality of child care tended to offset slightly the association between the amount of time in child care and children's behavior. Specifically, when children were in high-quality care, teachers were somewhat less likely to rate children in more hours of care as more aggressive than other children.
• When children were in center care, teachers were somewhat more likely to rate children who spent more hours in child care as more aggressive than other children. Nevertheless, the statistical links between time in child care and ratings of children's problem behavior were still evident even after quality of care, center care experience, and maternal sensitivity were taken into consideration.

The researchers concluded that children who experience long hours of child care over the first four years of life are at greater risk for being perceived as having behavior problems, particularly aggression, by adults. Not only were these children more likely to be perceived by adults as engaging in assertive, defiant, and even disobedient activities, but they were also more likely to be rated as children who bully, fight with, or act mean to other children.

The aggression and non-compliance/defiance reported were all mostly within the normal range. It is important to note, however, that 17 percent of the children who were in child care for more than 30 hours each week over their first four-and-a-half years of life were rated as being aggressive toward other children in kindergarten; only 6 percent of the children who were in child care for less than 10 hours per week on average were rated the same way. The researchers added that it is not yet possible to determine whether the children who were rated as aggressive will continue to show problems with aggression, as they grow older.

The researchers concluded that the findings of this study suggest a need for further discussion and debate concerning options such as family leave, flexible work schedules, and child care at the work place.