Table 5 Intervention Study Preregistered Hypotheses and their respective empirical corroboration

H1a (within-subject effect): Supported for conservatives in the meta-perception intervention.

B = 0.261, SE = 0.104, Wald χ²(1) = 6.23, p = 0.013

Significant increase in support for social equality after exposure to the meta-perception condition while controlling for pre-intervention support.

H1b (between-subject effect): Supported for conservatives in the meta-perception intervention.

B = 0.231, SE = 0.052, Wald χ²(1) = 19.74, p < 0.001

Conservatives in the meta-perception condition showed significantly higher post-intervention support than in the control condition.

H1c (meta-perception > other interventions)

Social norms: B = 0.206, SE = 0.111, p = 0.093. Malleability: B = 0.195, SE = 0.108, p = 0.192

Non-significant effect of social norms or malleability intervention on conservatives.

H2a (within-subject effect): Supported for centrists in the social norms intervention.

B = 0.334, SE = 0.108, Wald χ²(1) = 9.60, p = 0.002

Significant increase in support for social equality after exposure to the social norms condition while controlling for pre-intervention support.

H2b (between-subject effect): Supported centrists in the social norms intervention.

B = 0.312, SE = 0.097, Wald χ²(1) = 10.32, p = 0.001

Centrists in the social norms condition showed significantly higher post-intervention support than the control condition.

H2c (social norms > other interventions)

Meta-perception: B = 0.180, SE = 0.101, p = 074. Malleability: B = 0.072, SE = 0.105, p = 0.494

Non-significant effect of meta-perception or malleability intervention on centrists.

H3a (within-subject effect): Supported for liberals in the malleability intervention.

B = 0.267, SE = 0.086, Wald χ²(1) = 9.54, p = 0.002

Significant increase in support for social equality after exposure to the malleability condition while controlling for pre-intervention support.

H3b (between-subject effect): Supported for liberals in the malleability intervention.

B = 0.278, SE = 0.079, Wald χ²(1) = 12.21, p < 0.001

Liberals in the malleability condition showed significantly higher post-intervention support than the control condition.

H3c (malleability > other interventions)

Meta-perception: B = 0.037, SE = 0.098, p = 709. Social Norms: B = 0.150, SE = 0.099, p = 0.132

Non-significant effect of meta-perception or social norms intervention on liberals.

Full model: Time * Ideology * Intervention

Wald Chi-Square = 1403.019, p < 0.001

Effect of intervention on social equality varied across ideological groups, with significant differences in responses to conditions over time.