Catalyst for Change or Barrier to Health? A Meta-Analysis Synthesizing the Impact of Social Identity Threat in Health Messages

The use of social identity in health messaging is burgeoning, yet an open question remains as to whether appeals to one’s social identity can consistently promote health behavioral change. As an emerging field of inquiry, research on social identity threat in persuasive health messages remains fragmented. To address the inconsistent empirical findings, we conducted a meta-analysis to synthesize the existing research. Based on 18 independent studies from 12 articles (combined N = 4,436), the results indicated that, compared to non-threatening health messages, social identity-threatening health messages led to stronger perceived social identity threat (d = 0.231, p = .001), but yielded no significant effect on health behavioral intentions (d = −0.034, p = .541). Subsequent subgroup analyses revealed that threatening ascribed identities (e.g., race and gender) exerted a stronger impact than acquired identities (e.g., smoking and obesity). Furthermore, a significant and negative effect on health behavioral intentions emerged for non-stigmatized health topics, but the effect for stigmatized topics was nonsignificant. Our findings offer a nuanced account of social identity threat in health messages. Theoretically, perceived social identity threat merits operationalization as a standalone variable rather than a manipulation check criterion, which will enable future research to map out the boundary conditions of social identity-threatening health messages and unpack the mediating mechanisms underlying their persuasive impact. Practically, message designers should be mindful that identity-based appeals may backfire, particularly when addressing ascribed identities or non-stigmatized health topics.