A comparison of 193 pre-registered and 193 non-preregistered studies found no significant differences in positive results, effect sizes, or error rates¶

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

Subclaims¶

q2 i? Pre-registration did not differ from non-preregistration in proportion of positive results, effect sizes, or statistical error rates in a large paired comparison. → Ammar 2025

Evidence¶

Ammar 2025¶

Ammar, A., Trabelsi, K., Salem, A., Jahrami, H., & Schöllhorn, W. I. (2025). Advancing Contextual Interference: Addressing Methodological Debates, Reflecting on Meta-Analytic Practices and Generalizability, and Guiding Future Directions in Motor Learning. Educational Psychology Review. https://doi.org/10.1007/s10648-025-10043-1

q2 · i? · review · r2

The article cites von den Akker et al. (2024) second-hand to argue that pre-registration's practical impact may not meet expectations, supporting the claim that PRISMA treats registration as encouraged but not mandatory. The review reports this finding; its design details are not described here.

"a recent comparison of 193 pre-registered and 193 non-preregistered studies found no significant differences in the proportion of positive results, effect sizes, or statistical error rates (von den Akker et al., 2024)."

Discussion¶

Related Claims¶

• Author-reported statistically significant program effects did not remain significant after WWC corrections for clustering and multiple comparisons — related
• Registered reports were rated higher than typical papers on all nineteen evaluated quality criteria by 353 peer reviewers — related