A Critical Meta-analysis of All Evaluations of State-Funded Preschool from 1977 to 1998

January 2001

The study finds that preschool programs paid for by states improve children's readiness for school and lead to greater academic success. The paper provides numerous policy and evaluation recommendations for states implementing prekindergarten.

"A Critical Meta-analysis of All Evaluations of State-Funded Preschool from 1977 to 1998: Implications for Policy, Service Delivery and Program Evaluation"

Walter S. Gilliam and Edward F. Zigler (2001). Yale University Child Study Center. Early Childhood Research Quarterly, 15, 441-473.


This article provides a meta-analytic review of data from all completed evaluations of state funded preschool programs up to 1998. The authors critique the methods used for evaluation and provide measures of standardized effects for all the significant impacts. The authors found that although evaluations of state-funded preschool programs vary widely, enough data is present to suggest prekindergarten programs positively impact children in a number of areas.

Number of States Finding Positive Impacts of Pre-K by 3rd Grade*

*Only outcomes where at least three states examined effects are included.

This chart highlights the central findings that all states which studied these outcomes found prekindergarten programs had a positive impact on children’s overall development (7 of 7 states) and reduced grade retention in early elementary school (6 of 6 states). Most states that examined the issue also found prekindergarten positively affected attendance, grades, and achievement test scores. But most of the states did not find prekindergarten was linked to greater parental involvement or reducing special education referral and placement.

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