Purpose: Despite the availability and accessibility of standardized screening services, such as preventative health services, many individuals avoid participation. The extant health literature has indicated that health locus of control (HLOC) influences engagement and uptake of health services. The purpose of this paper is to explore how the microfoundation, HLOC, contributes to value co-creation via service-generated and self-generated activities in standardized screening services. Design/methodology/approach: A qualitative study of 25 consumers who have experienced one of the three standardized screening services in Australia was undertaken, followed by thematic analysis of the data. Findings: Service-generated activities elicit reactive responses from consumers – compliance and relinquishing control – but when customers lead co-creation activities, their active responses emphasize protecting self and others, understanding relationship needs and gaining control. Consumers with high internal HLOC are more likely to take initiative for their health, take active control of the process and feel empowered through participating. Consumers with low internal HLOC, in contrast, require more motivation for participation, including encouragement from powerful others through promotion or interpersonal dialogue. Social implications: These findings can be used by policymakers and providers of preventative health services for the betterment of citizen health. Originality/value: The integration of the DART framework, customer value co-creation activities, and the delineation of self-generated and service-generated activities provides a holistic framework to understand the influence of HLOC on the co-creation of value in standardized screening services.