This study develops a motivational interview and implementation intention intervention for blood donor retention and tests the efficacy of this new approach among first-time, Group O donors.

In this study the investigators will recruit first-time Group O- and O+ donors four weeks after their donation using the donor databases of New York Blood Center and Hoxworth Blood Center. Eligible donors will be contacted via email and invited to participate in the study. Interested donors will be randomly assigned to either the Intervention condition where they will receive a motivational interview and implementation intention intervention phone call or to the Control condition where they will receive a standard donor recruitment phone call. Outcome measures will be assessed before and after the telephone contact using online questionnaires, and donation attempts will be tracked for one year. The investigators will use survival analysis to examine the effects of this intervention on retention during this one-year follow-up. Path analyses will also be used to examine potential mediators of the intervention effect. The investigators hypothesis is that donors who receive the motivational interview and implementation intention intervention will have larger increases in positive donation attitudes and perceived behavioral control which will contribute to enhanced intention and donation attempts.

Inclusion Criteria:

• donor with New York Blood Center or Hoxworth Blood Center
• one previous donation
• O- or O+ blood
• eligible to donate again