The Red Blood Cell-Improving Transfusions for Chronically Transfused Recipients (RBC-IMPACT) study: protocol description of an international multi-site observational clinical study.

Karafin MS, Kelly S, Chapman KM, Kreuziger LB, Manis JP, Dinardo C, Josephson CD, Stone M, Roubinian NH, Branchford B, Sachais BS, Hailu B, Sabino EC, Hod EA, Custer B, National Heart, Lung, and Blood Institute (NHLBI) Recipient Epidemiology and Donor Evaluation Study-