. 2023 Jun 2;37(6):1441–1449. doi: 10.1007/s10877-023-01031-3

Table 3.

Masimo radical SpO₂ bias and A_RMS statistics for differences from SpO₂ at Hct = 40%

O₂Hb range	HCT = 30		HCT = 20		HCT = 10
O₂Hb range	Bias (%)	A_RMS (%)	Bias (%)	A_RMS (%)	Bias (%)	A_RMS (%)
60–69.9	0.04	0.04	0.27	0.28	3.76	3.83
70–79.9	0.01	0.02	0.54	0.54	1.85	1.89
80–89.9	− 0.06	0.06	0.77	0.78	0.95	0.95
90–100	− 0.15	0.15	0.97	0.97	1.05	1.07
70–100	− 0.07	0.10	0.76	0.78	1.28	1.37

For each device, the curve fit at hematocrit 40% was used as a “reference” performance level and was subtracted from the curve fits at hematocrits of 30%, 20%, and 10%. The bias (%) and A_RMS (%) were calculated over the 70–100% O₂Hb range and at each 10% O₂Hb range down to 60%. A_RMS is used to characterize pulse oximeter accuracy and A_RMS greater than 3% used as a threshold for inaccuracy