I've been thinking about child care recently as my daughter goes to daycare two days a week. Like many parents I read about the study that found kids in daycare centers had more behavioral problems later in school. There was a lot of media coverage of this finding, but the study was interesting in several other ways that didn't get much press.
Kids who spent time in child care also had higher vocabulary scores. Meara comes home with new words every time she goes to daycare. She also comes home with new words every time she goes to Nana's house, so I think it's about new and different sources of information.
The other funny aspect of the study is that they defined "child care" as anyone other than the mother spending significant time with the child. In other words, stay-at-home dads were counted as "child care.” This doesn't seem like the best definition, at least for my generation. I don’t have enough information to know how this affected the results of the study.
The final problem I see in the media coverage of this study is that the authors themselves said that the increase in vocabulary and problem behaviors was small, and that parenting quality was a much more important predictor of child development than was type, quantity, or quality, of child care. This confirms what most of us already suspected, that good parenting is what matters to kids, whether they spend time at daycare or not.