Table 1.

Hematocrit levels tested for all oximeters

Device	Nominal Hct level	N	Hct (%) Mean	Hct (%) StDev	Perfusion Index (%) Mean ± SD
Masimo Radical	40	6	39.2	0.20	8.1 ± 0.4
	30	7	30.5	0.17	6.7 ± 1.2
	20	7	20.5	0.13	5.4 ± 0.5
	10	9	10.1	0.18	3.4 ± 1.5
Acare AH-M1	40	8	40.0	0.30	–
	30	9	30.3	0.09	–
	20	8	19.7	0.05	–
	10	7	10.0	0.16	–
CMS 50-DL	40	8	40.5	0.42	–
	30	8	29.9	0.23	–
	20	9	19.9	0.30	–
	10	10	10.4	0.28	–

Hematocrit levels were estimated from the Total Hemoglobin (tHb) values measured on the Reference CO-oximeter using the relationship Hct ≈ 3*tHb. Perfusion Index (PI) was only provided for the Masimo radical. The Acare AH-M1 and CMS devices do not measure PI