Effects of a Statewide Prekindergarten Program on Children's Achievement and Behavior Through Sixth Grade
Durkin, K., Lipsey, M. W., Farran, D. C., & Wiesen, S. E. · 2022
grade Arctindependentunreplicatednumbers spot-checked
Sample
2,990 (RCT analytic sample)
Population
Tennessee Voluntary Pre-K applicants, lottery-randomised; a scaled STATE program meeting 9 of 10 NIEER quality benchmarks.
Design
The only randomised trial of a scaled state pre-K program followed to grade 6. CITE THE PUBLISHED CORRECTION (10.1037/dev0001407), which updated coefficients and odds ratios 'to the correct direction of effects'.
Key findings
A high-quality, fully scaled state pre-K program produced positive end-of-treatment gains that were gone by kindergarten and NEGATIVE by grade 6 on achievement, with more special-education placements and more disciplinary infractions. This is a randomised trial with a favourable counterfactual, which makes it very hard to dismiss.
Counterfactual
63% home/relative care, 13% Head Start, 16% private centre — i.e. a genuinely untreated majority, which should FAVOUR finding positive effects.
Genetic confound
Lottery-randomised — the cleanest design in the pre-K literature, and it produces the most uncomfortable result.
Replication notes
The single most important counterexample to extrapolating from Perry/Abecedarian. Not yet replicated at similar rigour in another state.
Cost
A fully funded state program meeting 9/10 NIEER structural quality benchmarks — quality is not the obvious explanation for the result.
DOI / URL
10.1037/dev0001301 (see correction 10.1037/dev0001407)
Effects
| Outcome | Metric | Value | Measure | Timing | Vs | Horizon | Class |
|---|---|---|---|---|---|---|---|
| Achievement, end of pre-K | ITT d | +0.236 (WJ Composite) — positive on all six cognitive tests | standardized | end-of-treatment | business-as-usual | end-of-treatment | domain-skill |
| Achievement, end of kindergarten | ITT d | +0.019 (ns) — fadeout complete within one year | standardized | end-of-treatment | business-as-usual | 1-2yr | domain-skill |
| Grade 6 math | ITT d (TOT) | -0.178 (-0.333), p<.001 — favours CONTROL | standardized | grade-6+ | business-as-usual | over-2yr | domain-skill |
| Grade 6 ELA | ITT d (TOT) | -0.128 (-0.240), p=.002 — favours CONTROL | standardized | grade-6+ | business-as-usual | over-2yr | domain-skill |
| Grade 6 science | ITT d (TOT) | -0.132 (-0.249), p=.002 — favours CONTROL | standardized | grade-6+ | business-as-usual | over-2yr | domain-skill |
| Special education (IEP) by grade 6 | rates | 11.7% treatment vs 8.4% control, p=.010 | standardized | grade-6+ | business-as-usual | over-2yr | attainment |
| Grade 6 discipline | rates | school-rule violations 23.1% vs 18.5%, p=.004 | standardized | grade-6+ | business-as-usual | over-2yr | behaviour |
Cited by
- Fadeout — why early gains disappear, and what actually persistsstrong supportconf: highgc: low
- Preschool at scale — Head Start, state pre-K, and what universal provision deliversmixedconf: highgc: low