If you are reading this article it is highly likely your child has been in preschool or will attend preschool. But pick randomly any child from US population, you will find that only 50% chance the child goes to preschool.

The rest either stay home, where they play with parents or caregivers, or attend daycare, which may not have an educational component. Preschool isn’t mandatory, and in most places it’s not free. (Source : WSJ)

What is the observed difference in their later performance of those who attended preschool and those who didn’t?

According to Dr. Celia Ayala, research says preschool attendance points to stellar career.  She said,

“Those who go to preschool will go on to university, will have a graduate education, and their income level will radically improve,”

50% of children don’t get to attend preschool because of economic disparity. Seems only fair to democratize the opportunities for these children and provide them free preschool when their parents can’t afford them.

I do not have a stand on fairness but I have a position on the reported research and how they drew such a causation conclusion.

First I cannot make judgement on a research when someone simply says, “research says”, without producing the work, the data that went into it and the publication. Let us look at two possible ways the said research could have been conducted.

Cross-sectional Analysis – Grab a random sample of successful and unsuccessful adults and see if there is statistically significant difference in the number of those who attended preschool.  As a smart and analytically minded reader you can see the problem with cross-sectional studies. It cannot account for all different factors and confuses correlation with causation.

Longitudinal Analysis – This means studying over a period of time. Start with some preschoolers and some not in preschool and track their progress through education, college and career.  If there is statistically significant difference then you could say preschool helped. But you, the savvy reader, can see the same problems persist.  Most significantly it ignores the effect of parents – both their financial status and genes.
A parent who enrolls the child in preschool is more likely to be involved in every step of their growth. Even if you discount that, the child is simply lucky to start with smart parents.

So the research in essence is not actionable. Using it to divert resources to invest in providing preschool opportunity to those who cannot afford is not only misguided but also overlooks opportunity cost of the capital.

What if the resources could actually help shore up elementary, middle or high-school in low-income neighborhood? Or provide supplementary classes to those who are falling behind.

Failing to question the research, neglecting opportunity costs and blindly shoveling resources on moving a single metric will only result in moving the metric but with no tangible results.

Where do you stand?