Table 4 Agreement between the first and second measures using the Boyd classification
From: Evaluation of mammographic density patterns: reproducibility and concordance among scales
Number of mammograms classified in each category in the first and second measurements | |||||||
|---|---|---|---|---|---|---|---|
Second measure | |||||||
First measure | A | B | C | D | E | F | Total |
A = 0% | 6 | 4 | 0 | 0 | 0 | 0 | 10 |
B = > 0-10*% | 4 | 56 | 11 | 0 | 0 | 0 | 71 |
C = 10-25*% | 0 | 16 | 50 | 13 | 0 | 0 | 79 |
D = 25-50*% | 0 | 0 | 14 | 102 | 9 | 0 | 125 |
E = 50-75*% | 0 | 0 | 0 | 14 | 48 | 6 | 68 |
F = ≥75% | 0 | 0 | 0 | 0 | 3 | 19 | 22 |
Total | 10 | 76 | 75 | 129 | 60 | 25 | 375 |
Kappa-statistic estimation | |||||||
Agreement | Kappa (95% CI) | Weighted Kappa (95% CI) | Kappa high/low risk (95% CI) | ||||
Observed % | Expected % | ||||||
74.93 | 22.88 | 0.675 (0.616-0.733) | 0.917 (0.898-0.933) | 0.822 (0.754-0.891) | |||