Fig 4.

4A. Bland-Altman plot showing the difference versus the average of bicarbonate (HCO₃) measured by the central Lab analyzer and by the POC Siemens RAPIDPoint 500 blood gas system. Bias, upper and lower limits of agreement (±1.96 SD) are represented. The red dotted line indicates equality (difference = 0). There is one marker for each patient. 4B. Scatter diagram showing Deming regression analysis for bicarbonate (HCO₃) measured by the central Lab analyzer and by the POC Siemens RAPIDPoint 500 blood gas system. The regression line (solid line) and the identity line (x = y, dotted line) are represented.