The Role of Prospection in Altruistic Bone Marrow Donation Decisions

Objective: The decision to become an unrelated allogeneic bone marrow or hematopoietic stem cell (HSC) donor is a consequential and complex one. Although new registry members pledge to donate if asked in the future, significant proportions ultimately reconsider when they are notified as a potential match for a patient and are asked to undergo confirmatory typing (CT), resulting in many patients failing to receive transplants. We consider the roles of prospection, or thinking about the future, and ambivalence, or having mixed emotions about an event, in this phenomenon. Prospection theory dictates that distant and improbable events are construed more abstractly than near-term and probable events. We hypothesized that construals about donation in new registry members versus those asked to undergo CT would differ in accordance with these patterns, and that variation in construals would be associated with decisions about whether to proceed toward donation. Method: In collaboration with the National Marrow Donor Program, we measured donation intentions and CT decisions in 516 new registry members and 213 members asked to undergo CT, respectively. Participants were asked to describe what they imagined would happen in the donation process. Results: We found that the valence and heterogeneity with which registry members construed donation were significant predictors of donation-related decisions. Assuming the temporal ordering of cognitive processes, ambivalence about donation was a mediator of these relationships. Conclusions: Findings suggest that encouraging a focus on positive central features of marrow and HSC donation may reduce ambivalence and decrease attrition from the registry.