Table 1:

Proportion of transfusions below a hemoglobin threshold of 80 g/L and population-based transfusion rates on the control and intervention units before and after the training intervention

Variable	Control site			Intervention site

	Before	After	p value	Before	After	p value
No. of transfusions	455	90	–	689	176	–

No. (%) of transfusions with hemoglobin concentration < 80 g/L^*	344 (75.6)	64 (71.1)	0.4	552 (80.1)	153 (86.9)^§	0.04

No. of patient days	36 678	10 774	–	40 454	11 149	–

No. of admissions	2873	851	–	3829	1101	–

No. of transfusions per 1000 patient days^†	12.4	8.4	< 0.001	17.0^§	15.8^§	0.4

No. of transfusions per 100 admissions^†	15.8	10.6	< 0.001	18.0^¶	16.0^§	0.2

↵* χ² test.
↵† Z-test of the rate difference with inverse variance weights.
↵§ p < 0.005 for comparison to control site during the same period.
↵¶ p = 0.03 for comparison to other site during the same period.