In the full-sample analysis, baseline demographic and prior-achievement differences between treatment and matched comparison groups were minimal, with effect sizes below the WWC threshold¶

Claim · All claims
Evidence · 1 study · causal r2 · q2
Currency · newest study 2025 · not yet checked against its sources · not reviewed by a person

Subclaims¶

q2 i? Baseline differences between treatment and matched comparison groups on demographics and prior math achievement were minimal, with effect sizes below the WWC required threshold. → Fong 2025

Evidence¶

Fong 2025¶

Fong, A., Chen-Gaddini, M., & Huang, M. (2025). An evaluation of the Air Tutors Program: Findings from an Arnold Ventures grant. WestEd. https://eric.ed.gov/?id=ED673538

q2 · i? · causal · r2

Baseline balance analysis for the full analytic sample (1,049 treatment students and 1,953 control students) after Mahalanobis matching on prior achievement, demographics, and program status. Differences on key demographic variables were "minimal, with effect sizes well below the WWC's required threshold," which the report says supports the validity of the full-sample analysis.

"Across all key demographic variables (e.g., gender, economic disadvantage, and English Learner status), differences between the treatment and control groups were minimal, with effect sizes well below the WWC's required threshold."

Discussion¶

Related Claims¶

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