Does childcare make children more stressed? : a meta-analysis of the effects of childcare on children’s cortisol levels

Abstract

Prior research has indicated that being in childcare causes children to be stressed. However, research on the effect of childcare on children’s stress levels, as measured by the hormone cortisol, has yielded inconsistent results. While some studies have found a strong positive association between childcare and increased cortisol levels, other studies have found no such association, or a negative association. The aim of this study was to review the literature and to perform two meta-analyses on the effect childcare has on children’s cortisol levels. A total of 10 studies (N=738) were reviewed and provided the basis for the analyses. I used two designs for the meta-analyses: the first design estimated an effect on a relative scale, and was based on a comparison of the difference between cortisol levels in the morning and afternoon for children at home compared to children in childcare. The second design estimated an effect on an absolute scale, and was based on comparing the average of the morning and afternoon cortisol levels of children at home compared to children in childcare. The findings of this study suggest that, on a relative scale, the cortisol levels of children in childcare did not decrease as much throughout the day as they did for children at home (d = 0:31, 95% CI [0.20, 0.41]). However, on an absolute scale, children in childcare did not display significantly higher cortisol levels on average than children at home (d = 0:06, 95% CI [ð€€€0:15; 0:26]). Overall, these findings suggest that the effect of childcare on children’s cortisol levels is to some extent present, but the effect size is arguably weak.