The goal of the REDS program is to evaluate and improve the safety and availability of the blood supply and the safety and effectiveness of transfusion therapies. The program also works to proactively address potential emerging threats to the Nation's blood supply and serves as a resource for ongoing work in transfusion research. Now in its fourth phase, the Recipient Epidemiology and Donor Evaluation Study-IV-Pediatric (REDS-IV-P) program aims primarily at improving the benefits of transfusion while reducing its risks; the REDS program also has a new focus on previously understudied populations. Over the past 30 years, REDS has been the premier research program in blood collection and transfusion safety in the United States. In its third phase — REDS-III — the program focused on conducting research on all elements of the transfusion chain, from the blood donor to the blood products made from their donation to the adult patients receiving the products through transfusion. REDS-IV-P builds on REDS-III with an additional focus on research with newborns, children, and pregnant women who need transfusions. The data compiled in REDS-IV-P will allow investigators to rapidly address key research questions in transfusion medicine and inform blood policy decisions, for adults as well as for children and other understudied patient populations. REDS-IV-P also extends the Brazilian sickle cell disease cohort that was established in REDS-III to evaluate transfusion practices and associated clinical outcomes in sickle cell disease. The REDS-IV-P Brazilian transfusion program will also continue its monitoring and surveillance efforts for Zika, chikungunya, dengue, and other emerging viral threats to the blood supply. This is the domestic hubs with database project protocols, with particular attention to the development of the statistical analytical plan. Conduct the statistical analysis for the database projects unless otherwise specified by the NHLBI COR. Provide the necessary statistical, epidemiological, and programming expertise as well as the necessary statistical software(s) to conduct analyses of genetic/phenotypic and “omics” data, and/or donors, donations, patient/recipient databases as well as the conduct of complex linked donor-recipient analyses, as appropriate.