Kaptoge S, Di Angelantonio E, Moore C, et al. - Among participants from a parallel group, pragmatic, randomized trial, the INTERVAL trial, which showed the safety of reducing inter-donation intervals for whole blood donation to meet blood shortages, researchers performed an extension study for a further 2 years to assess the longer-term risks and advantages of varying inter-donation intervals and to compare routine vs more intensive reminders to help donors keep appointments. Findings revealed that more blood was collected seemingly with no impact on donors' mental and physical wellbeing as a result of shorter inter-donation intervals and more intensive reminders, as seen over a period of up to 4 years. However, lower hemoglobin levels and more self-reported symptoms were identified in donors vs with the first 2 years of the trial. Findings support the safety of shorter donation intervals and more intensive reminders to meet shortages for donors who maintain adequate hemoglobin levels and iron stores.