Opponents of President Barack Obama's plan to increase access to quality preschool can criticize studies to support their political agenda, but science is on the side of advocates. Research demonstrating the benefits of preschool is strong and consistent.
Critics select a few studies out of the more than 100 conducted in the U.S. and find something wrong. For example, they reject the findings from Perry Preschool, the best known study of the long-term effects of preschool, because it was conducted a half-century ago. True enough, but its longevity has allowed researchers to compare participants to nonparticipants well into adulthood and document long-term effects.
Other studies are criticized because they did not use an ideal control group. Ideal experimental research designs -- what some in social science refer to as the "gold standard" -- require random assignment of children to preschool or not. It is very expensive and, given the strength of the evidence on the value of preschool, raises ethical concerns. The "regression discontinuity" design that they criticize -- in which children who just miss the age cutoff for eligibility are compared to children who just made it (adjusting for the month age difference) but are alike in all other relevant ways -- is a powerful and ethical research design that allows researchers to assess the effect of a year of preschool on children's readiness for kindergarten.
We can nitpick the research design of any one study, but all have pros and cons. Collectively research provides solid support for the value of preschool. A recent meta-analysis of more than 80 studies showed that children who had participated in an early childhood education program were about four months ahead in learning at the end of it. Studies showing significant positive effects include large-scale state preschool programs — the kind the Obama plan would expand — in such varied states as Arkansas, New Jersey, New Mexico, Oklahoma, Georgia and Michigan.
The unusually well-studied and large-scale Chicago Parent Child Program, funded by federal Title I funds, cost $6,730 (in 1998 dollars) for 11/2 years of participation and generated a total return to society of $47,759 per participant. Economic returns come in the form of reduced needs for special education, higher graduation rates, lower participation in the criminal justice system and higher earning capacity.
Another argument against expanding access to preschool is that if subsidized slots are not available, parents will find preschool alternatives for their children. The fact is that less than half of California's low-income children go either to state preschool or Head Start, and affordable alternatives are not available.
Most Americans have learned the value of providing children an opportunity to learn how to interact effectively with peers, pay attention to the teacher, regulate their emotions and behavior and develop the vocabulary and basic academic skills they need to succeed in increasingly demanding kindergarten programs.
A recent poll showed that 77 percent of registered voters said they support a federal early learning plan to help states and local communities provide better education without adding to the deficit. In fact, 86 percent surveyed said that "ensuring children get a strong start" is a top national priority, second only to increasing jobs and economic growth. And it's not just parents with preschool-age children who believe early childhood education should be a priority: 68 percent of respondents without children at home said they agreed this is a sound investment.
Misrepresentation of the research no doubt will continue, but fortunately, most Americans know better.
Deborah J. Stipek, Ph.D., is a professor of education at Stanford University and former dean. She wrote this for this newspaper.