Increasing organ donor registration rates by providing an immediate and complete registration opportunity: an experimental assessment of the IIFF model.

The IIFF model of organ donation holds that the simultaneous presence of four factors directly influence donor registration: (1) immediate and complete registration opportunity (ICRO), (2) information, (3) focused engagement, and (4) favorable activation. Two field experiments examined the impact of an ICRO on organ donation registration. In Study 1, participants were at town halls where they knew organ donation was to be discussed. Registration cards were distributed and then collected at the end of the session in half of the town halls. For the other half, participants were asked to mail in completed cards. In three US cities, participants given an ICRO registered at a significantly greater rate (z = 4.865, p < 0.05). Study 2, targeting Hispanics at a swap meet, differed in that the registration impact of awareness of the availability of an ICRO was investigated. Participants made aware of an ICRO registered at a significantly greater rate (z = 4.1, p = 0.000).