How children are affected by out-of-home care depends not only on the qualities of their teacher and the classroom, but also on the nature of the children's relationship with their caregivers.
That's the finding of a new study on the level of the stress hormone cortisol in children in full-day child care.
Cortisol, the primary stress hormone in humans, tends to be at its highest levels in the early morning and gradually declines over the course of the day. But recent research has found that many preschoolers in full-day child care have increases in cortisol from morning to afternoon.
This study found that children in classrooms with closer to 10 children were more likely to show cortisol decreases from morning to afternoon, while children in classrooms with closer to 20 children tended to show greater increases in cortisol across the day. Children with more clingy relationships with their teachers showed greater rises in cortisol from morning to afternoon, and children with more conflicted relationships with their teachers showed greater cortisol boosts during a one-on-one session with their teachers. Conflicted relationships were said to occur when teachers tried to control resistant children, when children perceived their teachers as unfriendly, or when teachers or children reported that the teachers found the interaction frustrating.
This unusual increase of cortisol levels is of potential concern because long-term or frequent elevations in cortisol can have negative health consequences. Research with animals and human children suggests that secure relationships with parents protect children from rises in cortisol in stressful situations.
This study, by researchers at Washington State University, Auburn University, the Washington State Department of Early Learning, and the Pennsylvania State University, appears in the November/December 2008 issue of Child Development .