Reviews restricted to peer-reviewed publications miss unpublished findings.

Evidence

Even though the selection criteria ensure that the selected studies are substantively relevant and academically high-quality, the selection process is limited in two ways. On the one hand, we only study published works of research. As Erzeel and Rashkova (2022) rightly mention, published work benefits from recognition from peers in the field, and ensures that quality-standards are met. However, this inevitably means that potentially valuable, but not yet published, studies are not included. — Didier Caluwaerts et al., Deliberation and Polarization, 36

Categorization

• XREF: connects to: Subjective literature reviews suffer selection biases that meta-analysis avoids. — Thomas F. Pettigrew, Linda R. Tropp, A Meta-Analytic Test of Intergroup…, 28; Comparing published and unpublished studies tests whether reporting bias inflates effects. — Thomas F. Pettigrew, Linda R. Tropp, A Meta-Analytic Test of Intergroup…, 109; Meta-analyses overestimate effect sizes because null results go unpublished. — Thomas F. Pettigrew, Linda R. Tropp, A Meta-Analytic Test of Intergroup…, 44 (+3 more)

Broader Connections

• Meta-analyses overestimate effect sizes because null results go unpublished. #corroborates (0.90) — Thomas F. Pettigrew, Linda R. Tropp, A Meta-Analytic Test of Intergroup…, 44
• Comparing published and unpublished studies tests whether reporting bias inflates effects. #expands (0.85) — Thomas F. Pettigrew, Linda R. Tropp, A Meta-Analytic Test of Intergroup…, 109
• Personal quarrels and practical losses suppressed publication of a prescient study #exemplifies (0.85) — Martin Jay, The Dialectical Imagination, 393
• Publication bias explains apparent effects in alternative medicine research. #exemplifies (0.82) — Holm Gero Hümmler, Ulrike Schiesser, Fact and Prejudice, 770
• Institutional resistance delayed publication of a correct clinical observation by thirteen years. #exemplifies (0.82) — , The Rod and the Child, 9524
• Subjective literature reviews suffer selection biases that meta-analysis avoids. #qualifies (0.75) — Thomas F. Pettigrew, Linda R. Tropp, A Meta-Analytic Test of Intergroup…, 28