A preliminary study evaluating cardiac output measurement using Pressure Recording Analytical Method (PRAM) in anaesthetized dogs

Table 4 Results of 4-quadrant plot and polar plot

	TDCO vs PRAMCO
Measurements < 10% (n)	11
Measurements > 10% in the right quadrants (n)	34
Measurements > 10% in the wrong quadrants (n)	3
Total measurements > 10% (n)	37
Concordance rate (%)	92
Mean angular bias (°)	3.9
Radial limits of agreement (°)	± 12.1

Concordance rate was calculated as: 100 × (data points in correct quadrant and > 10% CO)/data points > 10% CO. Concordance rates are considered to be good when above 95%, acceptable when between 90 and 95% and poor when below 90%. In the polar plot a mean angle with the horizontal axis < 5° and radial limits of agreement RLOA (= 95% confidence interval) < 30° are considered to indicate good trending ability

ISSN: 1746-6148