Vaccination attitude theory and methods: opportunities for replication, generalization, and valid synthesis science

To help understand Covid-19 vaccination decisions, research has focused on studying attitudes. The research has promised to inform behavioral interventions that will increase vaccination rates and thereby decrease related mortality and morbidity. These important public health goals depend on studies with valid definitions, operationalizations, and analyses of vaccination attitudes using systematic and transparent methods. We consider the degree to which Covid-19 vaccination attitude research is contributing to these goals and how the research can benefit from adopting psychology's established, rigorous approaches. We focused on foundational Covid-19 vaccination attitude research, generating a pool of 464 articles, and randomly selecting approximately half ( n = 232) for detailed, manual review, of which 23 qualified for the final content analysis. The final content analysis assessed and compared the ways in which studies theoretically and methodologically investigate vaccination attitudes. We report that nearly all articles (21/23, 91.30%) forgo a definition of attitudes and conflate this construct with other constructs, including knowledge, intention, and behavior. With two exceptions (2/23, 8.70%), the articles measure attitudes using methods that are unclear or fundamentally incompatible with each other and established, validated methods. Only two articles (2/23, 8.70%) apply attitude theory to guide the study's selection of variables and analyses. The results reflect several threats to the study of vaccination attitudes that may delay critically important insights. Potential remedies include a shared definition and theoretical conceptualization of the attitude construct, which would help ensure that the same phenomenon is investigated. We describe how this research can adopt psychology's standardized, validated approaches to studying attitudes. Standardized, validated methods would not only strengthen individual studies but also support conceptually aligned and theoretically informed synthesis science.