Few prejudice reduction experiments show strong evidence of widespread success.

Evidence

From science to lasting change We note that partisan animosity is a specific example of a broader phenomenon: intergroup prejudice113. A recent review of 418 prejudice reduction experiments, including extended and imaginary contact, cognitive and emotional training, social categorization, and other methods, found that few studies demonstrated strong evidence of widespread success179 (political prejudice was excluded from the review). The authors of that review suggest that many issues contribute to the disconnect between promising research and long-term prejudice reduction, including publication bias, small sample sizes and short-term outcomes. We suspect that many of these issues may apply to the studies we discuss here. Many interventions show promise in controlled, small-scale studies, but the most successful interventions need to be effective (have reliable, large effects), durable (have long-lasting effects), broad (influence partisans across the political spectrum) and scalable (be practically applicable in real-world settings). — Rachel Hartman et al., Interventions to Reduce Partisan…, 71

Categorization

• XREF: Directly benchmarks against the 2025 PNAS depolarization-is-hard finding and the reader’s broader catalog of intervention skepticism. — connects to: Randomized contact experiments yield near-large prejudice reduction effects. — Thomas F. Pettigrew, Linda R. Tropp, A Meta-Analytic Test of Intergroup…, 121; Anti-prejudice programs can successfully target institutional rather than only individual bias. — , Rudman, Laurie A - On the Nature of…, 2672; More rigorous contact studies show larger prejudice-reduction effects. — Thomas F. Pettigrew, Linda R. Tropp, A Meta-Analytic Test of Intergroup…, 120 (+1 more)
• ADDENDUM: Relevant framing companion for the depolarization interventions catalog thread.

Broader Connections

• Randomized contact experiments yield near-large prejudice reduction effects. #contradicts (0.82) — Thomas F. Pettigrew, Linda R. Tropp, A Meta-Analytic Test of Intergroup…, 121
• More rigorous contact studies show larger prejudice-reduction effects. #contradicts (0.80) — Thomas F. Pettigrew, Linda R. Tropp, A Meta-Analytic Test of Intergroup…, 120
• Anti-prejudice programs can successfully target institutional rather than only individual bias. #qualifies (0.74) — , Rudman, Laurie A - On the Nature of…, 2672
• Reducing prejudice requires qualitative social change, not individual fixes alone #qualifies (0.72) — , Rudman, Laurie A - On the Nature of…, 1418