Does social capital explain community-level differences in organ donor designation?

The shortage of organs for transplantation has reached unprecedented levels. Organ donor registration rates vary widely despite both national and state campaigns to increase donations.

"We found that community-level sociodemographic and social capital variables explain more than half the variation that we observed in organ donor registrations in Massachusetts," said first author Keren Ladin, Ph.D., M.Sc., an assistant professor and health policy researcher in the department of occupational therapy at Tufts University's Graduate School of Arts and Sciences. "Neighborhoods that have lower social capital, as measured by high levels of both racial segregation and violent crime, and low socioeconomic status and voting participation, also have lower levels of organ donor registration compared to other Massachusetts neighborhoods."

The factors that appear to have a positive relationship to increased donor registrations include higher income, employment and owner-occupied housing. The findings also suggest that when populations are less isolated and better racially integrated, they exhibit higher rates of altruistic behavior such as organ donor registration.

The authors point out that the study reinforces the importance of tailored messages at the neighborhood level and strategic partnerships with community-based organizations in the effort to increase organ donor designation.

Using 3.3 million geocoded records from the Massachusetts Registry of Motor Vehicles that were linked to sociodemographic data from the U.S. Census, Ladin and colleagues obtained community-level measures and social capital characteristics including residential segregation, voter registration and participation, residential mobility, violent-death rate and religious characteristics.

The combined data included 4,466 Massachusetts neighborhoods and used geospatial modeling to account for the spill-over of adjacent block groups and multivariate regression analysis to examine the relationship of social capital and community-level characteristics with organ donor registration rates.

"Research has focused on individual-level determinants, without much consideration for contextual factors, such as neighborhood environment and social organizations. A better understanding of these contextual determinants of organ donor registrations, including social capital, may enhance efforts to increase organ donation. The findings may help explain differences in rates of organ donor registration among communities of color and suggest that interventions tailored to communities, rather than individuals, may help to increase organ donation," said Ladin.

"Like voting or vaccination, organ donor designation is a collective action problem. The community benefits are significant, but individual incentives to participate are low. Social capital increases the probability of collective action by fostering norms of reciprocity and cooperation while increasing the costs of noncompliance," she continued.

Ladin is also an assistant professor in the department of public health and community medicine at Tufts University School of Medicine and director of the lab for Research on Ethics, Aging, and Community Health in the occupational therapy department and community health program at Tufts.

More than 120,000 Americans are waiting for organ donations, according to the Organ Procurement and Transplantation Network.