Elicitation of moral obligation and self-sacrificing behavior: an experimental study of volunteering to be a bone marrow donor.

It was hypothesized that self-sacrificing behavior is positively related to the salience of consequences for others and to the salience of the actor's personal responsibility in an appeal for help, and negatively related to the odds of incurring costs. Theoretically, the former two variables promote activation of moral norms, while the latter fosters neutralization of norms. These variables were manipulated in appeals to 144 subjects in a field experiment to donate bone marrow. Volunteering increased with responsibility (p <.05), but was unrelated to odds. The relationship between volunteering and consequences under 1/25 odds was curvilinear, with high salience of consequences producing the lowest rate of volunteering. To explain this curvilinear relationship, it was proposed that psychological reactance is expressed overtly as refusal when pressure in an appeal seems illegitimate. Volunteering was positively related to socioeconomic status (p < .01). The strikingly high rate of volunteering is traced to the momentum of compliance.