Table 2.

Unadjusted mortality rates according to quartiles of maximum age of red cells

Quartile	Age of RBCs (days)	Mortality
		All patients	APACHE III scored
1	7.7 (2 to 11)	25/189 (13.2%)	24/185 (13.0%)
2	13.8 (11 to 18)	41/189 (21.7%)	40/175 (22.9%)
3	22.6 (18 to 28)	36/189 (19.1%)	34/176 (19.3%)
4	34.4 (28 to 42)	44/190 (23.2%)	43/177 (24.3%)
2 to 4	22.7 (11 to 42)	121/568 (21.3%)	117/528 (22.1%)

Values expressed as median (range) or number/total (proportion). RBC, red blood cell; APACHE, Acute Physiology and Chronic Health Evaluation.