Comparing published and unpublished studies tests whether reporting bias inflates effects.

Evidence

Finally, as a direct test for publication bias, we compare (in Table 2) the negative mean effect sizes between intergroup contact and prejudice from published sources (journals and books) and unpublished sources (dissertations, conference papers, and other unpublished manuscripts). — Thomas F. Pettigrew, Linda R. Tropp, A Meta-Analytic Test of Intergroup…, 109

Categorization

• SEED: The published-versus-unpublished mean effect comparison is a neat, teachable methodological template for any meta-analysis write-up.
• XREF: connects to: Publication-status differences in priming effects disappear once correlated design variables are controlled. — Annetta Snell and Miron Zuckerman and Bonnie M. Le, Does Religious Priming Induce Greater…, 84; Industry cherry-picking is continuous with ordinary scientific publication bias — Cailin O’Connor and James Owen Weatherall, The Misinformation Age: How False…, 359; Contact’s prejudice-reducing effect is causal, not a selection or publication artifact. — Thomas F. Pettigrew, Linda R. Tropp, A Meta-Analytic Test of Intergroup…, 216

Related

• Meta-analyses overestimate effect sizes because null results go unpublished. (similarity 0.89)
• The intergroup contact-prejudice link survives file-drawer checks, indicating limited publication bias. (similarity 0.88)
• The contact-prejudice effect may be partly an artifact of publication bias. (similarity 0.87)
• Publication-status differences in priming effects disappear once correlated design variables are controlled. (similarity 0.87)
• Publication bias can be detected through sample-size and effect-size correlations. (similarity 0.86)
• Contact’s prejudice-reducing effect is causal, not a selection or publication artifact. (similarity 0.86)
• Publication bias inflates the apparent effectiveness of prejudice-reduction programs (similarity 0.85)
• The publication effect on priming prejudice results vanishes once confounding moderators are controlled (similarity 0.84)
• More rigorous contact studies show larger prejudice-reduction effects. (similarity 0.82)
• Stronger contact effects in rigorous studies would confirm the contact-prejudice link. (similarity 0.82)
• Religious priming’s apparent prejudice effect exists only in published studies. (similarity 0.81)
• No meta-analysis of intergroup contact research existed before this study. (similarity 0.81)
• Randomized contact experiments yield near-large prejudice reduction effects. (similarity 0.81)
• The fail-safe index underestimates publication bias by assuming missing studies have no effect. (similarity 0.81)
• A null correlation between sample size and effect size indicates minimal publication bias. (similarity 0.80)