A new experimental approach to manipulate social identity and social norms about protective behaviors in a virtual social environment

Focus theory of normative conduct and social identity theory propose that the degree of social identification with a group moderates the influence of social norms on behavior. The current study protocal reports two studies testing this causal assumption in the context of health protective behaviors during a health crisis using a newly developed experimental manipulation of both social identity and social norms regarding protective behaviors during a health crisis in a virtual social environment. A new virtual social environment was co-created with Citizen Scientists and will be used in two experiments covering several online sessions to test (a) the manipulation of social identity, and (b) the manipulation of social norms regarding protective behaviors in a simulated health crisis (Study 1: using a vignette approach; Study 2: using the virtual social environment). The main outcome is adherence to protective behaviors (Study 1: self-reported; Study 2: behavior within the virtual social environment). We successfully developed and implemented the virtual social environment using a Citizen Scientist approach. The Citizen Scientists report high overall participation experiences co-creating the virtual social environment, as well as high learning gains in coordinating with others, using GitHub/Git, and game mechanics. Both studies will provide insights into (1) the development of a virtual social environment in collaboration with Citizen Scientists, (2) methods for experimentally manipulating social identity and social norms, and (3) the causal mechanisms linking social identity, and social norms to protective behaviors. We expect that the findings inform methodological approaches for experimentally simulating social situations that typically lay outside experimental control (here: a health crisis) and assessing health-related behaviors, future Citizen Science-based approaches, and theory on social influence on behavior during a health crisis. The trial registration ID is ISRCTN97703902. We registered the studies with ISRCTN on February 6, 2025, with the last update on March 5, 2025.