Do all material incentives for pro-social activities backfire? The response to cash and non-cash incentives for blood donations

A number of experimental studies have documented that financial rewards discourage the performance of altruistic activities because they conflict with intrinsic altruistic motivations. However, it is unclear whether this is evidence of a generalized aversion to rewards or, rather, an aversion to receiving specific material prizes, such as cash. We conducted a randomized-controlled experiment, through a survey administered to 467 blood donors in an Italian town, and found that donors are not reluctant to receive compensation in general; a substantial share of respondents declared that they would stop being donors if given 10 Euros in cash, but we do not find such effects when a voucher of the same nominal value is offered instead. The aversion to direct cash payments is particularly marked among women, but does not emerge among individuals who have only recently become donors. All of our findings are robust to regression analyses. Implications for research and public policy are discussed.