Fourteen of the 15 studies showed a reduction in the number of units transfused per patient10,14,16- 20,25- 28 or the number of units transfused14,17- 18,20- 23,28 (range of relative reduction, 9%-77%). The 1 study34 that did not show a reduction in the total number of units transfused reported a reduction in the number of inappropriate transfusions. For the remaining studies, the range of the relative reduction was similar for RBCs10,16,18- 20 (range, 12%-65%) and FFP17,20- 23,26 (range, 9%-77%), but lower in studies examining platelets17,20,28 (range, 14%-23%) (Table 3). However, in the studies17,20,25,27 that reported the effectiveness of an intervention on the number of platelets transfused and at least 1 additional product, the relative reductions after the interventions were similar for platelets and other product(s) studied. Six (43%) of the 14 studies10,17- 19,25,27 used statistical tests to determine whether the changes in the number of units transfused were significant. In 4 (67%) of these studies,10,17- 19 the reduction was significant for all blood products studied. Two studies25,27 reported both significant and nonsignificant reductions for different blood products. The first study27 reported a significant reduction in the number of units of cryoprecipitate per patient per month and nonsignificant changes for RBCs, FFP, and platelets. In the second study,25 the reduction in number of units transfused per patient per month was significant for RBCs and platelets, but not FFP. The other 9 studies14,16,20- 23,26,28,34 did not determine the statistical significance of the changes in blood product utilization. Two (22%) of these 9 studies26,34 did not observe a reduction in utilization for all products studied. One study26 reported a reduction in the number of units of FFP transfused, but no change in the number of units of platelets transfused. As noted previously, the other study34 reported an increase in the number of units of FFP transfused, but a reduction in inappropriate transfusions.