The relative efficacy of three interventions to favour return to give blood.

BACKGROUND: The aim of the study was to test the relative efficacy of action planning and reward distribution to promote retention of whole blood donors.

MATERIALS AND METHODS: A sample of 7,399 donors was randomised to one of three interventions: "action planning" (n=2,585); "reward" (n=2,397); and "thank you" (n=2,417). Participants in the action planning condition were invited to write the date of their next donation on a post-it note before taking it home at the end of the donation process. Participants in the "reward" condition were given an anti-theft credit card sleeve at the end of the donation process. The "thank you" intervention is the usual condition at the end of the process; it was considered the control condition. The dependent variable was the proportion of donors who registered to give blood at six months.

RESULTS: Overall, 4,444 (60.06%) donors registered to give blood at six months. There were no differences between the three interventions in the proportions of donors who registered to give blood (d.f. 2, chi-square=3.72, p<0.15). However, gender modified the effect of the intervention (d.f. 2, chi-square=6.57, p<0.0375); more women registered in the "thank you" condition than in the other two.

DISCUSSION: The results suggest that action planning and the distribution of a reward have no motivational effect on the return to give blood. Nonetheless, women appear to respond more negatively to these interventions at the end of the donation process.