Written By Melinda Wenner Moyer for Slate
In its cover story a few weeks ago, the New York Times Magazine followed up with nearly two dozen mothers who had decided, a decade ago, to walk away from successful professional careers to stay home with their kids. Although none of these moms outright regret their choices, many wish they had at least continued to work part-time. Career options dry up, it seems, the longer you forgo them.
For me—the parenting columnist—the elephant in the room when I read the article was: So what was best for their kids? Parents often decide to stay home because they think doing so is better for their children. (Sure, there are plenty of other reasons, too, such as the desire to be around one’s offspring and, oh yeah, the crippling costs of child care.) But is this notion—that kids do better when a parent, typically a mother, stays home with them—actually true?
Ooh boy, does the Internet have a lot to say about this. But few articles I found presented much scientific evidence; it was hard to distinguish the trustworthy from the tripe. I did, however, find far more articles written by women who defended day care—sometimes very emotionally—than who warned against it. Was this imbalance, I wondered, driven by evidence or rationalization?
I dug into the science to find out. There’s quite a lot of research on the issue, which isn’t surprising considering how ubiquitous child care is in this country: According to the U.S. Census, 16 percent of babies under the age of 1 are enrolled in center-based day care, while 26 percent of 1- to 2-year-olds are. Adding in family-based day care—day care out of someone's home—and nannies, 33 percent of children under age 5 are regularly cared for by nonrelatives. This figure doesn’t even include the 18 percent of kids who have multiple child care arrangements.
Before I tell you about the findings, I need to share a bit about my own situation. My son is in full-time day care. (Otherwise, you wouldn’t be reading this.) I tried my damnedest not to let my own situation cloud my reporting for this column, but it’s hard to objectively assess research on an issue about which one has already made an irreversible decision. I read studies I didn’t like and subconsciously tried to pick them apart; I read studies I liked and didn’t want to do the same; I was brought close to tears in interviews; other times I felt enormous waves of relief. Ultimately, after coming to peace with my child care decisions (and I’ll tell you how I did that later), I think I assessed the literature clearly, or at least as clearly as journalist who happens to also be a mother possibly could.
What I found is that day care can be good (primarily for cognitive development), and day care can be bad (by making kids more aggressive and impulsive)—and the good seems to become less helpful the more educated and well-off parents are. But this is important: It’s impossible to predict how day care is going to affect an individual child, like, you know, your actual kid. It may have certain effects on average, but most researchers I talked to speculate that its effects are concentrated in a subset of children. “It’s not going to mean that each child is going to have 0.05 percent probability of being more aggressive,” explains Aletha Huston, a professor emeritus at the University of Texas at Austin, who was involved in one of the largest, longest-running studies on the effects of child care on development, the National Institute of Child Health and Human Development’s (NICHD) Study of Early Child Care and Youth Development, which followed more than 1,000 kids from infancy to age 15 starting in 1991. “What probably is represented here is that some kids are responding in that way, and a lot of kids aren’t.”
As Huston’s comment also suggests, the effects, on average, are small. What’s far, far, far more important than child care in shaping your kid’s future is what her home life is like. Jay Belsky, a child development expert at the University of California, Davis, who was also involved in the NICHD study, put it to me this way: “If you were a fetus and the good Lord came to you and said, ‘I can give you great quality day care and a lousy family, or a great family but lots of lousy day care,’ you choose the latter, not the former.” Yet in the same breath, Belsky added that even though the negative effects of day care are modest, “one needs to be careful about dismissing them.”
Let’s tease out these positive and negative effects, when they happen, and what might be causing them. Multiple studies, including the NICHD study, have found that, after statistically adjusting for the effects of social class and other potential confounders, kids enrolled in high quality child care given by nonrelatives develop slightly better cognitive and language skills—as measured at various points in their lives, all the way up through age 15—than do kids in low-quality care. These beneficial effects are more pronounced for low-income kids than children from more affluent families and for kids in center-based care than other types of care. The NICHD study also compared children in child care to children who stayed at home with their mothers for the first three years of their lives, and the ones at home fared somewhere in the middle: They scored better on verbal comprehension tests at age 3 than did kids in low-quality care, but they scored worse on language tests at age 2 than kids in medium- and high-quality care. Interestingly, studies suggest that the cumulative amount of time kids spend in care makes little difference when it comes to scores; what matters is whether they go at all and if it’s good or bad. That said, there were differences when the NICHD researchers parsed out the ages for which child care was used. Kids who spent a lot of time in care in infancy had worse academic achievement at age 4½ than did kids who spent little time in care in infancy, but kids who spent more time in care during their toddler years scored better on language tests than kids who were home more during their toddler years. Is your head spinning yet?
Obviously one key question is what it means that kids in higher quality care develop “slightly better cognitive and language skills.” I asked around, and although researchers were loath to give specifics, Belsky said it might mean a few points on a standardized test. “Good quality care wasn’t changing the course of mighty rivers and turning average kids into geniuses,” he explains. Again, although the effects are small on average, it’s possible that some kids experience more significant benefits. As for what distinguishes good care from bad: One crucial factor is how caregivers interact with the kids. Are they responsive and sensitive? Do they get down on the floor with the children or are they always standing in the back, looking bored? Higher quality care also tends to have a higher ratio of adults per child, fewer children per group, and staff is typically more highly educated.
As for the downside of day care: several studies, including those using the NICHD’s data, have found that the more time kids spend in day care (and especially center-based care rather than, say, family day care), the more behavioral problems they develop later as reported by teachers. These effects include being more disobedient through age 4½ (and through the sixth grade for kids from center-based care); having poorer academic habits and social skills in the third grade; and being more impulsive and taking more risks at age 15. Again, the experts I talked to couldn't give specifics on how big these effects were, but one reassured me that the behavior of day care kids is still usually well within the normal range. Many—but not all—of the studies suggest that these problems develop even after high quality care, so quantity really seems to be the crux of the problem, yet there doesn't seem to be a threshold where these effects start, either—it's not that 20 hours a week doesn't cause any problems but 22 does. Some studies do, however, suggest that certain kids—those, for instance, with “difficult” temperaments—are more sensitive to quality than others, in that they are more likely than other kids to develop behavioral problems from low-quality care and can even glean social benefits from high-quality care.
It’s important to keep in mind some of the (major) limitations of these studies. They were designed to find associations, not cause-and-effect relationships. Parents who use day care differ in many ways from parents who don’t. Yes, there are stay-at-home moms found in all income brackets, and both poor and affluent families put kids in day care. Still, on average, parents who use day care tend to have higher incomes and fewer kids than those who don’t. They are “much more advantaged in almost every way,” says Margaret Burchinal, a senior scientist in the Frank Porter Graham Child Development Institute at the University of North Carolina at Chapel Hill, who was also involved in the NICHD study. Affluent families tend to enroll their kids in higher quality day care, too (although don’t assume your day care is awesome just because you’re paying a fortune for it: The majority of day care in this country is mediocre).
This means that studies on the effects of child care compare different types of families to one another, not just differences in child care use—and as I mentioned before, the former is a much more significant influence on kids than the latter. Although studies try to control for the impact of education and income and the like, this so-called selection bias “is a huge factor,” Burchinal says, and it’s unclear, exactly, how these confounders might impact results. On the one hand, one could imagine that the better home life of advantaged kids might mask or compensate for the negative effects of day care, but on the other hand, the benefits of group care may be smaller for these kids, too (for more on this idea, read my preschool column). Interestingly, when researchers compared how well children fared if their mothers did or did not go back to work before their first birthday and then broke results down by race, they found that full-time work in the first year by white, non-Hispanic mothers was associated with poorer cognitive development in their kids through the first grade, but that full-time work by African-American mothers was not. It’s unclear exactly why.
It’s easy to imagine why day care might boost language scores—I know my kid interacts with lots of people all day long. But the causes of the negative effects are still a head scratcher. Day care doesn’t, for instance, seem to disrupt the mother-child attachment bond. One possible answer Belsky provides is group size: The NICHD data suggest that the more kids a child spends time with in day care, the more unruly he becomes, but the evidence on this isn’t clear-cut, either. Huston notes the types of kids in a child’s group might make a difference—if your kid is spending time with a bunch of brats, he might turn into a brat too. Other work suggests that America's heavy use of early day care (we're one of the few countries with parental leave policies requiring kids to be put into care as young infants) could be a problem, since good baby and toddler care requires a high ratio of staff to kids and centers aren't always willing to pay for that. Or, others say, maybe there's just something about the cultural climate in the U.S. that makes day care more harmful here, because studies have shown that day care in Norway, which has much more supportive family policies (and better day care), causes few, if any, social problems. One of Belsky’s concerns, which is backed by a study, is that the negative effects of day care here in the U.S. might compound in grade school, in that classrooms comprised mostly of kids from day care might be poorer learning environments than classrooms made up mostly of kids who stayed at home, because all the little behavioral effects will add up and teachers will end up spending their time trying to control their students rather than, you know, teaching.
So what’s a parent to take from all this—particularly one whose child is in day care all the time? My first instinct was to cry; my second was to attach a camera to my son’s shirt to see what his days were really like; my third was to get really, really pissed at our government for not doing more to ensure that U.S. child care is higher quality. (U.S. child care workers earn less than janitors and amusement park attendants. Outrageous, right?) But there’s another aspect to this body of research that I haven’t mentioned yet, and it’s reassuring, at least to me. In addition to collecting data on child care use and income and the like, researchers with the NICHD also asked mothers—both those who used day care and those who did not—questions about how they felt about day care. Should a mom stay home with their kids, they asked, or should she feel comfortable using group care and going back to work? When moms said it was better for mothers to stay home with their kids, and these mothers did stay home with their kids, their children fared very well. When moms felt that it is OK to work and put kids in child care, and these moms did work and put their kids in child care, their kids did great too. In other words, “when the mother’s choice was congruent with what she wanted and believed, children did well,” Burchinal says. What’s best for you, then, may well be what’s best for your kids, too.
In addition to the sources mentioned, The Kids would also like to thank Jane Waldfogel at Columbia University and Katherine Magnuson at the University of Wisconsin at Madison.