Meta-analytic average Cronbach's Alpha of domain-specific knowledge tests is 0.85 with expected item intercorrelation of 0.22¶

Claim · All claims
Evidence · 1 study (2 entries) · quant-synthesis r2–r3 · q3
Currency · newest study 2025 · not yet checked against its sources · not reviewed by a person · recheck by 2028: tool and model accuracy changes quickly

Subclaims¶

q3 i? The meta-analytic average Alpha of domain-specific knowledge tests is 0.85, CI90 [0.82, 0.87], exceeding the hypothesized range of 0.70–0.75. → Peter A. Edelsbrunner 2025 q3 i? The expected average item intercorrelation of knowledge tests is 0.22, consistent with the hypothesis that it would be below 0.30. → Peter A. Edelsbrunner 2025 (2)

Evidence¶

Peter A. Edelsbrunner 2025¶

Peter A. Edelsbrunner, Bianca A. Simonsmeier, Michael Schneider. (2025). The Cronbach’s Alpha of Domain‑Specific Knowledge Tests Before and After Learning: A Meta‑Analysis of Published Studies. Educational Psychology Review. https://doi.org/10.1007/s10648-024-09982-y

q3 · i? · quant-synthesis · r3

Cluster-robust random-effects meta-analysis of 285 effect sizes from 55 samples of knowledge tests reporting Alphas before and after learning. The estimated average Alpha was 0.85 with 90% CI [0.82, 0.87], described as against Hypothesis 1 which predicted 0.70–0.75.

"the overall estimate from the cluster-robust random-effects meta-analysis was Alpha = 0.85, with a 90% confidence interval (CI) of [0.82, 0.87]"

Peter A. Edelsbrunner 2025 (2)¶

Peter A. Edelsbrunner, Bianca A. Simonsmeier, Michael Schneider. (2025). The Cronbach’s Alpha of Domain‑Specific Knowledge Tests Before and After Learning: A Meta‑Analysis of Published Studies. Educational Psychology Review. https://doi.org/10.1007/s10648-024-09982-y

q3 · i? · quant-synthesis · r2

Derived from the meta-analytic Alpha using the Spearman–Brown formula. The expected item intercorrelation was "rexp = 0.22, 90% CI [0.18; 0.25]", in line with Hypothesis 2 predicting rexp < 0.30, though the broad PI indicates substantial heterogeneity.

"This estimated intercorrelation was rexp = 0.22, 90% CI [0.18; 0.25], with a 90% prediction interval (PI) of 90% PI [0.03, 0.57]"

Discussion¶

Related Claims¶

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