Comparison of organ donation and transplantation rates between opt-out and opt-in systems.

Studies comparing opt-out and opt-in approaches to organ donation have generally suggested higher donation and transplantation rates in countries with an opt-out strategy. We compared organ donation and transplantation rates between countries with opt-out versus opt-in systems to investigate possible differences in the contemporary era. Data were analysed for 35 countries registered with the Organisation for Economic Co-operation and Development (17 countries classified as opt-out, 18 classified as opt-in) and obtained organ donation and transplantation rates for 2016 from the Global Observatory for Donation and Transplantation. Compared to opt-in countries, opt-out countries had fewer living donors per million population (4.8 versus 15.7, respectively) with no significant difference in deceased donors (20.3 versus 15.4, respectively). Overall, no significant difference was observed in rates of kidney (35.2 versus 42.3 respectively), non-renal (28.7 versus 20.9, respectively), or total solid organ transplantation (63.6 versus 61.7, respectively). In a multivariate linear regression model, an opt-out system was independently predictive of fewer living donors but was not associated with the number of deceased donors or with transplantation rates. Apart from the observed difference in the rates of living donation, our data demonstrate no significant difference in deceased donation or solid organ transplantation activity between opt-out versus opt-in countries. This suggests that other barriers to organ donation must be addressed, even in settings where consent for donation is presumed.