WASHINGTON — The more time that kids spent in day care, the more likely their sixth-grade teachers were to report problem behaviors such as getting in fights, being disobedient in school and arguing a lot, according to the largest study of child care and development ever conducted in the United States.
But quality of day care and overall parenting were still bigger predictors of child development. For instance, those who got high-quality child care before entering kindergarten had better vocabulary scores in the fifth grade than did youngsters who received lower-quality care.
The 1,364 children in the analysis had been tracked since birth as part of a study by the National Institutes of Health.
The study triggered controversy in 2001 when it found that children who were in child care were more likely to be aggressive and defiant in kindergarten. Monday’s study follows them into the fifth and sixth grades. The researchers found that the vocabulary and behavior patterns did continue, but there were no differences in math, reading or other skills.
Both the negative and positive effects were subtle, said Dr. James Griffin, who oversaw the study.
“If you went into one of these classrooms, you wouldn’t be able to say, 'this child, this child and this child attended center-based care,'" Griffin said.
Child development expert Barbara Bowman said the findings shouldn't add to guilt parents may feel about their kids spending time in day care.
“Although there is a slight difference between children who have been in child care and children who have not, we don’t know what it means or how significant it is in terms of the children's subsequent achievement and adjustment in life," said Bowman, professor and co-founder of Chicago’s Erikson Institute, a child development graduate school. "It is interesting, but it is not a big, big deal."
The researchers also assessed the quality of parenting. Griffin said attention from parents is far more important to how a child turns out than day care or schooling.
In the study, child care was defined as care by anyone other than the child’s mother who was regularly scheduled for at least 10 hours per week.
The researchers have measured the quality, quantity and type of child care the children received from birth until they were 4-1/2 years old.
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Quality child care is complex to define but includes having trained caregivers and a low child-to-caregiver ratio.
“I think the bottom line on this one is that we are still showing the effects of quality, so you want to look as much as possible to make sure it is accredited, that the teachers have a strong background in child development,” Griffin said.
The researchers said the enduring effect of child-care quality is consistent with other evidence showing that children’s early experiences matter to their language development.
The long-term effect on behavior also may have a logical explanation, the researchers said.
“One possible reason why relations between center care and problem behavior may endure is that primary-school teachers lack the training as well as the time to address behavior problems, given their primary focus on academics,” the researchers said.
More research is needed to understand why behavior problems continue so many years after the actual child care, said Bowman, who is also chief executive of early childhood education at Chicago Public Schools.
Children who spend more time at home may be more attuned to what adults want, she suggested. On the other hand, children who spend longer time in child care may be taught more independent thinking, which could cause problems for teachers.
"What we really need to do now is identify children in preschool and follow them into [school] and see what the dynamics of the behavior problems are that the teachers are complaining about. Let’s go back and see if we can account for the behavior," she said.
The study appears in the current issue of Child Development. The authors emphasized that the children’s behavior was within a normal range.
Still, the differences in behavior do merit more study, particularly on classroom and playground dynamics, the authors said.
“We regard (the behavior) as noteworthy and meaningful because of the large number of children in America who experience extensive and/or low-quality child care prior to school entry,” they said.
The Associated Press and Reuters contributed to this report