The impact of age and sex on first-time donor return behavior.

While older first-time donors are more likely to return and return more quickly than middle-aged donors they make up only a small proportion of first-time donors, whereas the larger group of younger donors exhibits less clear patterns of return compared to middle-aged donors. Further research is needed to determine whether targeting the recruitment of older donors or bolstering retention of middle-aged donors would be most effective in maintaining the blood supply.