Why do people (not) donate their data? A scoping review on factors influencing participation in data donation studies and strategies to enhance it

Data donations have recently emerged as research method, partly enabled by legislation such as the GDPR. A relevant challenge they face are low participation rates, which can introduce bias and limit the potential of data donations to harness digital trace data for studying behavior in various contexts. We conducted an interdisciplinary scoping literature review to map research on participation in data donation studies, outlining factors that might discourage participation and strategies to address these issues. To ensure methodological clarity, data donations are defined by clear criteria: The donation is an active and unpaid, but at times incentivized, transfer of intangible, reproducible, and retrospective, trace data. Furthermore, data donations are voluntary and informed, and primarily motivated by contributing to the common good. Based on this definition, which also served as the inclusion criteria for our study, we analyzed 30 studies. Included literature predominantly focuses on health research and hypothetical scenarios, exploring attitudes rather than actual donations. Although the investigated literature is diverse, several factors are discussed to influence willingness to donate. These include respondent characteristics such as gender differences and technical skills, situational factors such as privacy concerns and motivations including egoism, study-related attributes including required data types and who receives the data, and societal-level factors such as contextual influences and culture. Strategies to increase willingness include general approaches like offering benefits and the right communication, as well as study design–related strategies, particularly cultivating trust, e.g., through credible collaborations and appropriate privacy protection.