Motivating first-time, group O blood donors to return: Rationale and design of a randomized controlled trial of a post-donation telephone interview

First-time blood donors are essential to the US donor pool, providing nearly a third of all donations. Unfortunately, there are a wide variety of obstacles to repeat donation and new donors are extremely difficult to retain. Because each donor experiences a unique set of deterrents, we developed a post-donation interview based on motivational interview principles in order to flexibly address individual barriers. The primary aim of this randomized clinical trial is to examine retention of first-time, group O blood donors who are randomly assigned to receive either a telephone-delivered interview with motivational and action planning components or a standard-of-care control call approximately six weeks after their donation. Measures of donation attitude, perceived behavioral control, intention, and motivational autonomy will be measured before and after the telephone contact using online surveys, and donation attempts will be tracked for one year using blood center donor databases. We hypothesize that, compared to controls, donors who receive the telephone interview will be more likely to make a donation attempt over the following year. In addition, we will examine possible mechanisms of action of the interview using key predictors of donation behavior as described by Self Determination Theory (i.e., motivational autonomy) and the Theory of Planned Behavior (i.e., attitude, perceived behavioral control, and intention). Results of this intervention may help to support a novel strategy to enhance retention of selected blood donors in an effort to better meet the nation's blood supply needs.