Table 2. Influence of temperature and blood flow on MFPF P_O2 measurements: Linear regression model.

	Non-standardized coefficients			95.0% CI
Independent variable	Regression coefficient	Standard error	P-value	lower limit	upper limit
Temperature (base 20 °C)
Constant	−2.335	10.483	0.825	−23.744	19.074
PO2-magnitude [(MFPF + CTE)/2]	0.062	0.027	0.031	0.006	0.118
30°C	12.854	11.466	0.271	−10.563	36.271
40°C	19.635	11.392	0.095	−3.629	42.9
Blood flow (base 0.8 L min−1)
Constant	−4.707	2.401	0.058	−9.586	0.171
PO2-magnitude [(MFPF + CTE)/2]	0.045	0.004	<0.001	0.037	0.054
1.6 L min−1	−4.461	2.441	0.076	−9.422	0.5
2.4 L min−1	−2.822	2.262	0.221	−7.42	1.776
3.2 L min−1	−2.093	2.328	0.375	−6.825	2.638
4.0 L min−1	−5.188	2.171	0.023	−9.601	−0.776

Linear regression model: magnitude of P_O2 measurements, temperature and blood flow as independent variables, differences of P_O2 measurements as dependent variable. P_O2  =  oxygen partial pressure; MFPF  =  Multi Frequency Phase Fluorimetry; CTE  =  Clark-type electrode; CI  =  confidence interval.