The campaign season always seems to bring discussion about government's role in supporting day care. Those in favor of greater government subsidies point to the burden that day care's high cost creates for struggling working families. Those opposed to these proposals usually focus on the costs for taxpayers and our growing national debt. Almost never considered are the non-monetary costs to the children when large subsidies induce their parents to put them in day care.

The prevailing narrative about day care is that negative behaviors of day-care children fade over time and are balanced out by cognitive gains for day-care children compared to children cared for at home. Yet this near consensus persists in part because journalists and developmental psychologists are reluctant to acknowledge research findings that conflict with this comforting narrative.

Persuasive studies about the effects of child care are difficult to find. Most rely on observational data in which researchers collect information about children and families and then try to control statistically for variables such as family income, mother’s educational level and the quality of the day care. Yet the conclusions derived from this type of study are often found to conflict with the findings of more exacting experiments.

The gold standard for empirical social science is when subjects are randomly placed into either a treatment or a control group. Of course, such experiments on day care will never occur because parents won’t allow researchers to randomly pick whether their children are cared for at home or a day care center.

But there is research that, while not randomized, yields many of the benefits of this experimental design. These studies have not received serious attention.

Consider what researchers have found about the experience with child care in Quebec, Canada. Between 1997 and 2000, Quebec began heavily subsidizing day care so that parents had to pay only $5 per day out of pocket. The program increased child-care use in Quebec by more than one third. Studies have compared children’s well-being in Quebec before and after this change and made comparisons with other Canadian provinces that didn’t embrace a policy to subsidize child care.

The first of these studies found “striking evidence that children’s and family outcomes [in Quebec] have worsened since the program was introduced. This was manifested in increased aggressiveness and anxiety for the children; more hostile, less consistent parenting for the adults; and worse adult mental health and relationship satisfaction.” 

More recent studies confirm the profound negative effects of the Quebec child-care program. While the researchers found “little impact on cognitive test scores,” the anxiety, aggression, and hyperactivity became worse as the children became older. There was “a worsening of both health and life satisfaction among those older youths exposed to the Quebec child care program.” Moreover, there was a startling increase in criminal behavior among teens.  

Other worrisome studies find children younger than 3 show increases in the stress hormone cortisol when at day care, but not when the same children are at home on the weekend. One of the studies notes that elevated cortisol levels are “often interpreted as boding ill for physical and emotional health.”

In animal studies, daily exposure to even relatively minor stressors in infants leads to adult animals who exhibit heightened fearfulness and greater vulnerability to stressors.

Though developmental psychologists try to reassure them, Americans remain skeptical about day care. A 2014 Pew survey found that 60 percent of Americans think that it is best for children if one parent stays home. And a March 2013 Pew study found that just 16 percent of mothers say that having a mother who works full-time is best for children.

We don’t mean to demonize families who use day care.  Many parents have little choice, and one of us has children in day care part-time. Like millions of other parents, she believes it is the best option for her family in balancing different considerations such as cost, convenience, and the desire to support a work life as well as the well-being of her children.

But more parents would have more choices if our public policies supported families with young children more broadly, whether the parents worked full-time, part-time or not at all. 

Since two-parent, single-earner families make substantially less income than two-earner families, and since these families are making financial sacrifices to make possible what they think and what the public thinks is the best child care for young children — i.e., one parent staying home — why should they not benefit from any increased subsidy for families with children? Across-the-board financial relief may make it possible for some parents working full-time to switch to part-time work or even stay home, while also providing financial assistance to those paying for day care.

Increasing the dependent tax credit substantially would benefit all parents with children. Such a policy change would be expensive, however, so policymakers should consider how to further target that relief to those who need it most.

Making the dependent tax credit apply to Social Security taxes as well as income would help the working poor. Moreover, since most concerns about day care are focused on children under the age of 3, the dependent deduction could be primarily increased for families with the youngest children.

Regardless of the worth of these policy proposals, parental and program decisions should be made in full awareness of the research showing the risks to children from day care in their early years. Ignoring or downplaying these studies impedes the development of good public policy, and disserves society — particularly our children.  

Carrie Lukas is a mother of five and the managing director of Independent Women’s Forum; Steve Rhoads is professor emeritus of politics, University of Virginia and author of “Taking Sex Differences Seriously.” This article is adapted from a piece in the summer issue of National Affairs.