According to the American Red Cross, only 3% of the US population donates blood. A systematic review of 29 studies, published in the journal Transfusion Medicine Reviews, found that interventions to promote blood donation which focus on psychosocial cognitions, altruism or reminders were the most effective. Face-to-face contact and telephone solicitations were the most effective delivery modes. The authors noted that further study may be warranted to assess the efficacy of newer communication technologies..
Godin G, Vezina-Im LA, Belanger-Gravel A, Amireault S. Efficacy of interventions promoting blood donation: a systematic review. Transfus Med Rev 2012;26: 224-37 e6.