In other words, the higher-than-average incidence of bad behavior showed up only among kids who spent three or four years in day care before the age of 4½. Burchinal and her co-authors used a behavior measure on which a score of 50 is exactly average (and the higher the score, the brattier the kid). The mean score of kids who spent one or two years in day care before kindergarten was 50. The mean for kids who spent three years was 51.4. The mean for kids who spent four years was 52. Kids who spent no time at all in day care had a mean score of 49.6—lowest, yes, but to an extremely small degree. Also, only 5 percent of the kids in the study spent four years in day care, and only 10 percent spent three years.
Here's a key question: What was the quality of the day care this 15 percent received? Were their centers as good? Burchinal ran the numbers for me, and the answer is no. The study rated all child-care arrangements on a scale from 1 for abysmal to 4 for excellent. The mean score for kids who were cared for entirely at home was 2.85. The mean for kids who spent less than a year in day care was 2.84. One to two years in day care: 2.82. Three to four years: 2.76. And four or more years: 2.71. In other words, the kids with more reported behavior problems in elementary school were the ones who spent three or four years in day care and whose care was, on average, of lower quality.
The differences in quality of care among all settings are small, and the correlation between a longer time spent in day care and a reduction in the quality of care is modest. But then the uptick in bad behavior scores is slight, too. "We found that more time in day-care centers correlates to higher problem behavior scores," Burchinal said. "This raises the question whether it could be the quality within those centers" that accounts for the effect.
Burchinal points out that on average, day care for infants and toddlers is worse than for preschoolers. It's more expensive because states require more staff for babies. And the littlest kids don't get much out of being in a group like the older ones do. The youngest thrive on one-on-one attention, and it takes considerable skill and experience to deftly juggle the needs of a bunch of them. So maybe the real lesson here is a reminder: Day care for infants and toddlers is the hardest to do well. And lower-quality care, coupled with three or four years spent at a center, doesn't appear to serve kids quite as well as other arrangements (though the difference in slight).
This is not exactly heartening. Day care for infants and toddlers is often the most economical choice for families in which both parents work and no grandparent or cousin can lend a hand with the baby. We should figure out how to improve day care for infants and toddlers, not give up on it. Still, the study's results, properly explained, do not suggest that kids who spent a year or two in day care when they are 3 and 4—or, in my opinion at least, kids who go to excellent day care for longer periods—will talk back to their teachers and throw more than their share of spitballs when they get older. These kids will behave themselves just fine. As long as their parents don't screw them up.
I would say that this comes as a relief, since each of my own two sons spent (or in 4-year-old Simon's case is spending) four years in day care before kindergarten. Except that I stopped taking the bad rap on day care personally a long time ago.
There is an enormous difference between excellent day care and mediocre day care—when Simon had one year of the latter, believe me, I could tell. But that distinction, crucial as it is to the kids who experience it and to their parents, often is lost on the rest of the world. One day when my older son Eli was about 2, he charmed the woman ahead of us in line at the supermarket. They grinned and goo-goo-ed at each other, and then Eli's new friend turned to me with a big smile and said, "He must be at home with you." I stammered no and started babbling: Eli was in day care, but it was really wonderful day care, with only 12 kids and five teachers, and really if you visited him there you would see … But the woman's smile had vanished. We stood in embarrassed silence until her groceries were bagged. It probably doesn't matter what the data really show. Day care is supposed to be bad for kids, so it is. The headlines don't change.