Evaluation of mammographic density patterns: reproducibility and concordance among scales

BMC Cancer

Table 2 Agreement between the first and second measures using the Tabár classification

Number of mammograms classified in each category in the first and second measurements
	Second measure
First measure	II	III	IV	V	Total
II	12	9	0	0	21
III	4	170	16	8	198
IV	0	4	114	6	124
V	0	8	9	15	32
Total	16	191	139	29	375
Kappa-statistic estimation
Agreement		Kappa (95% CI)	Weighted Kappa (95% CI)	Kappa high/low risk (95% CI)
Observed %	Expected %
82.93	40.05	0.715 (0.649-0.772)	0.707 (0.623-0.781)	0.800 (0.739-0.861)

Low risk categories:
I: Mammogram composed of scalloped contours with some lucent areas of fatty replacement and 1 mm evenly distributed nodular densities.
II: Mammogram composed almost entirely of lucent areas of fatty replacement and 1-mm evenly distributed nodular densities.
III: Prominent ducts in the retroareolar area.
High risk categories:
IV: Extensive, nodular and linear densities with nodular size larger than normal lobules.
V: Homogeneous ground-glass-like appearance with no perceptible features.

ISSN: 1471-2407