Can inactive blood donors be re-recruited? A stratified randomised pilot study.

Objective: The aim of this study was to evaluate the effectiveness of recruitment of inactive donors by telephone call and cell phone short message service (SMS), to assess the causes of donor self-deferral and to determine the appropriate sample size for a formal study 

Background: Blood donor retention is essential for sustaining blood safety and sufficiency. 

Methods: We conducted a single-centre open-label parallel randomised controlled trial in Guangzhou, China. A total of 1188 inactive donors with the last donation between 2009 and 2013 were enrolled and randomly assigned to two intervention groups (telephone call and SMS groups) and one control group without any intervention. Donors were followed up for 7 months; their responses including donation activities were analysed. 

Results: The re-donation rates among the three groups were statistically significantly different (P = 0.044), particularly between the phone call group and the control group (P = 0.017). Within the phone call group, the re-donation rate was positively associated with the frequency of prior donation (P = 0.026), and the age of the donors (P = 0.043). Medical issues, time constraints and group donation were the main causes of self-deferral. The appropriate sample size for each group for a formal study to detect difference between the phone call and SMS groups was estimated to be 1429 participants. 

Conclusions: Our findings suggest that active interventions, especially phone call reminders, can increase blood donation. Further studies are required to compare the efficacy and effectiveness between phone call and SMS reminders using a larger sample size.