Bryant ongoing.

Trial name or title	Strategies to reduce iron deficiency (STRIDE) study
Methods	A multi‐centre, randomised, double‐blind, parallel, efficacy study
Participants	Frequent blood donors: 3 or more (men) or 2 or more (women) donations in the prior 12 months
Interventions	Treatment arm 1: donors given a letter thanking them for donating Treatment arm 2: donors given a letter informing them of their plasma ferritin level and recommending action to prevent iron deficiency, such as taking iron supplements or delaying donation Treatment arm 3: donors given 60 placebo pills following each donation Treatment arm 4: donors given 60 pills with 19 mg elemental iron (the amount in a typical multiple vitamin with iron) following each donation Treatment arm 5: donors given 60 pills with 38 mg elemental iron following each donation
Outcomes	Efficacy (specific outcomes not reported)
Starting date	Not reported
Contact information	B J Bryant, Blood Bank, University of Texas Medical Branch, Galveston, Texas, United States. Email: bbryant@utmb.edu
Notes	Enrolment of 660 donors complete; study now entering the 2‐year longitudinal follow‐up phase