Unpacking drivers of public health and science politicization: dimensions of news messages and cognitive pathways of influence

Abstract

Although the political underpinnings of public health and science are well recognized, these domains are increasingly politicized, with public-facing messaging often strategically framed to highlight controversy and political connotations. Beyond serving short-term political interests, such messaging can undermine public health and scientific agendas, contributing to adverse societal outcomes including diminished trust in public institutions and experts. Prior empirical investigations indicate that exposure to politicization in the public sphere elicits negative emotions, confusion regarding health and science information, and reduced support for policies aimed at promoting public well-being. Despite the significance of its consequences, empirical understanding of how politicization unfolds and affects public responses remains limited, in part due to conceptual ambiguity and insufficient attention to the psychological processes triggered by encounters with politicizing messages. This dissertation addresses these gaps by separately examining the effects of two dimensions of politicization—conflict/controversy (operationalized as news messages that feature controversy) and political discourse/cues (operationalized as news messages that feature political context)—on affective, cognitive, and policy support outcomes, and by evaluating two mediating variables—perceived controversy and perceived political connection—as potential psychological antecedents in the causal pathway. Two studies employed an identical cross-sectional experimental design testing a parallel mediation model in which exposure to politicizing messages shapes perceptions of controversy and political connection, which in turn influence emotional, cognitive, and policy support responses. Study 1 (N = 580) examined these dynamics in the context of gas stove safety, while Study 2 (N = 1,078) provided a conceptual replication using the contexts of per- and polyfluoroalkyl substances (PFAS) and mammography screening. In each study, participants were randomly assigned to read a news message featuring one, both, or neither dimension of politicization, with posttests assessing the proposed mediators and key outcomes.Results indicated that messages emphasizing controversy reliably increased perceived controversy, whereas messages emphasizing political context primarily enhanced perceptions that political actors discuss the featured topic. Stronger perceptions of controversy and political actor discussion were generally associated with heightened negative emotions and cognitive responses, whereas greater perceptions of the topic’s public relevance—unaffected by message manipulations—were linked to reduced confusion and backlash and greater support for policy measures. Indirect associations, estimated via a measurement-of-mediation approach, suggested that perceived controversy and perceived political actor discussion may mediate the effects of politicizing messages. Adverse outcomes were generally more pronounced in response to messages featuring controversy than to those emphasizing political context. While many associations and patterns of effects replicated across topics, some exhibited topic-specific variation. Overall, findings advance conceptual clarity for the study of health and science politicization, identify perceptions of controversy and political actor discussion as potential psychological antecedents through which effects of politicizing messages operate, and may inform future public health and communication interventions designed to counteract the negative consequences of politicization in the public sphere.