Best-Quality Vessel Identification Using Vessel Quality Measure in Multiple-Phase Coronary CT Angiography

Table 4

Agreement between radiologist 1 and the automated selection using VQM of the best-quality branch in the corresponding vessel pairs, between radiologist 2 and the automated selection, and between the two radiologists estimated in terms of the commonly used categories based on Cohen’s kappa statistics [8].

	Kappa
	Rad 1-computer	Rad 2-computer	Rad 1-Rad 2
Case  1	Almost perfect	Substantial	Almost perfect
Case  2	Almost perfect	Almost perfect	Substantial
Case  3	Substantial	Moderate	Substantial
Case  4	Moderate	Moderate	Substantial
Case  5	Fair	Fair	Substantial
Case  6	Fair	Fair	Slight
Case  7	Slight	Less than chance	Fair
Overall	Moderate	Moderate	Moderate

Agreement categories based on Cohen’s kappa statistics [8].
Kappa < 0: less than chance agreement.
Kappa 0.01–0.20: slight agreement.
Kappa 0.21–0.40: fair agreement.
Kappa 0.41–0.60: moderate agreement.
Kappa 0.61–0.80: substantial agreement.
Kappa 0.81–0.99: almost perfect agreement.