Estimating Tanzania's National Met and Unmet Blood Demand From a Survey of a Representative Sample of Hospitals

Abstract

Estimating blood demand to determine collection goals challenges many low-income countries. We sampled Tanzanian hospitals to estimate national blood demand. A representative sample based on probability proportional to size sampling of 42 of 273 (15%) Tanzanian transfusing hospitals was selected. Blood bank registers, patient medical records, and blood component disposition records were reviewed prospectively from June to September 2013 to determine the number of components requested and the number and proportion issued, not issued due to nonavailability, and not issued for other reasons. Data were estimated for an annual national estimate. Of an estimated 278 371 components requested in 2013, 6648 (2.4%) were not issued due to nonavailability, 34 591 (12.4%) were not issued for other reasons, and 244 535 (87.8%) were issued. Of these 278 371 components, 86 753 (31.2%) were requested by adult medical, 74 499 (26.8%) by pediatric medical, and 57 312 (20.6%) by obstetric units. In these 3 units, the proportion of units not issued due to nonavailability was 1.8%. Private (4.1%) and large (6%) hospitals had the largest proportion of units not issued because of nonavailability. Of 244 535 issued components, 91 690 (37.5%) were collected, tested, and issued from blood banks that are not part of the Tanzania National Blood Transfusion Services (TNBTS). Nearly 98% of blood component demand was met. However, a large portion of the blood supply for the hospitals came from non-TNBTS blood banks. TNBTS could increase availability of safe blood through assuring the quality of donor selection and donation testing at non-TNBTS blood banks.

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