Cross-cultural investigation of the relationship between social identity, trusting the system, COVID-19 vaccine adherence and conspiratorial beliefs

Understanding how individual beliefs and societal values influence support for measures to prevent COVID-19 transmission and risk is vital to developing and implementing effective prevention policies. Surges in COVID-19 infections continue to be prevalent worldwide, and strategies to address the increase in vaccine hesitancy and related conspiracy theories are enacted globally. Using the lenses of the social identity approach and system justification theory, we examined how individual-level conceptualizations of identity, system legitimacy, conspiracy beliefs and trust in science, government and healthcare influence an uptick in COVID-19 vaccine adherence. Data from an international survey of adults from China, the Philippines and the United States (N = 358; Study 1) and a six-country two-wave stratified online sample (N = 6138; Study 2) allowed the present research to investigate how cultural values and governmental policies intersect with COVID-19 risk perception and vaccine hesitancy. The most robust findings were: (1) identifying with a superordinate global identity was associated with greater vaccine adherence; (2) having a stronger subordinate national identity was associated with greater vaccine hesitancy; and (3) the association between having a strong national identity and the endorsement of COVID-19 conspiracy theories was mediated by system justification. The results presented are used to discuss strategies for increasing vaccine uptake globally for future pandemics.