Table 3.
Screening performance measures in total and within volpara density grade (VDG) categories (based on the available views)
| Screening performance measures (95% CI) for total population and within VDG breast density categories | p trend | |||||
|---|---|---|---|---|---|---|
| Total | VDG 1 | VDG 2 | VDG 3 | VDG 4 | ||
| Total | ||||||
| Recall/1000 | 21.8 (20.9; 22.7) | 15.2 (13.7; 16.8) | 21.7 (20.2; 22.9) | 24.8 (23.1; 26.6) | 30.7 (27.2; 34.5) | <0.001 |
| FP/1000 | 15.9 (15.1; 16.6) | 11.2 (9.9; 12.6) | 15.1 (14.0; 16.2) | 18.2 (16.8; 19.8) | 23.8 (20.8; 27.3) | <0.001 |
| Screen-detected cancer/1000 | 6.0 (5.5; 6.4) | 4.0 (3.2; 4.8) | 6.4 (5.7; 7.2) | 6.6 (5.7; 7.5) | 6.8 (5.3; 8.8) | <0.001 |
| Interval cancer/1000 | 2.1 (1.9; 2.4) | 0.7 (0.4; 1.1) | 1.9 (1.5; 2.3) | 2.9 (2.3; 3.5) | 4.4 (3.2; 6.0) | <0.001 |
| BC/1000 | 8.1 (7.6; 8.7) | 4.6 (3.8; 5.6) | 8.3 (7.5; 9.1) | 9.4 (8.4; 10.5) | 11.2 (9.2; 13.6) | <0.001 |
| Sensitivity of screening (%) | 74.0 (71.1; 76.7) | 85.7 (78.1; 91.0) | 77.6 (73.2; 81.5) | 69.5 (64.1; 74.4) | 61.0 (51.2; 70.0) | <0.001 |
| Specificity (%) | 98.4 (98.3; 98.5) | 98.9 (98.7; 99.0) | 98.5 (98.4; 98.6) | 98.2 (98.0; 98.3) | 97.6 (97.2; 97.9) | <0.001 |
| PPV (%) | 27.3 (25.6; 29.1) | 26.2 (21.9; 30.9) | 29.9 (27.1; 32.8) | 26.4 (23.5; 29.6) | 22.3 (17.7; 27.6) | 0.12 |
| Only invasive tumors taken into account | ||||||
| Recall/1000 | 20.6 (19.8; 21.4) | 14.3 (12.9; 15.9) | 20.5 (19.2; 21.8) | 23.3 (21.7; 25.1) | 28.5 (25.2; 32.3) | <0.001 |
| FP/1000 | 15.9 (15.1; 16.6) | 11.2 (9.9; 12.6) | 15.1 (14.0; 16.3) | 18.3 (16.9; 19.8) | 23.9 (20.9; 27.4) | <0.001 |
| Screen-detected cancer/1000 | 4.7 (4.3; 5.1) | 3.1 (2.5; 3.9) | 5.4 (4.8; 6.1) | 5.0 (4.3; 5.9) | 4.6 (3.4; 6.2) | 0.02 |
| Interval cancer/1000 | 2.1 (1.9; 2.4) | 0.6 (0.4; 1.0) | 1.8 (1.4; 2.2) | 2.8 (2.3; 3.5) | 4.4 (3.2;6.0) | <0.001 |
| BC/1000 | 6.9 (6.4; 7.3) | 3.7 (3.0; 4.6) | 7.2 (6.5; 8.0) | 7.9 (7.0; 8.9) | 9.0 (7.2; 11.1) | <0.001 |
| Sensitivity of screening (%) | 69.1 (66.5; 73.0) | 83.3 (74.3; 89.6) | 74.4 (70.2; 79.4) | 62.9 (58.1; 69.8) | 50.6 (40.5; 61.9) | <0.001 |
| Specificity (%) | 98.4 (98.3; 98.5) | 98.9 (98.7; 99.0) | 98.5 (98.4; 98.6) | 98.2 (98.0; 98.3) | 97.6 (97.2; 97.9) | <0.001 |
| PPV (%) | 23.0 (21.3; 24.7) | 21.7 (17.6; 26.3) | 26.3 (23.6; 29.2) | 21.6 (18.9; 24.7) | 16.1 (12.1; 21.2) | 0.02 |
| Only subsequent screening rounds taken into account | ||||||
| Recall/1000 | 17.9 (17.0; 18.7) | 13.5 (12.1; 15.2) | 18.2 (16.9; 19.5) | 20.1 (18.4; 21.9) | 21.9 (18.5; 25.9) | <0.001 |
| FP/1000 | 12.4 (11.7; 13.1) | 9.7 (8.4; 11.0) | 12.1 (11.1; 13.2) | 14.2 (12.8; 15.7) | 16.3 (13.3; 19.9) | <0.001 |
| Screen-detected cancer/1000 | 5.5 (5.0; 6.0) | 3.9 (3.1; 4.8) | 6.1 (5.4; 6.9) | 5.9 (5.0; 6.9) | 5.6 (4.0; 7.8) | 0.02 |
| Interval cancer/1000 | 2.2 (1.9; 2.5) | 0.7 (0.4; 1.2) | 2.0 (1.6; 2.5) | 3.1 (2.5; 3.9) | 4.3 (2.9; 6.3) | <0.001 |
| BC/1000 | 7.7 (7.2; 8.3) | 4.6 (3.8; 5.6) | 8.1 (7.3; 9.0) | 9.0 (7.9; 10.2) | 9.9 (7.7; 12.7) | <0.001 |
| Sensitivity of screening (%) | 71.3 (68.6; 75.1) | 84.3 (76.0; 90.1) | 74.8 (70.1; 79.8) | 64.4 (59.2; 71.3) | 56.7 (44.1; 68.4) | <0.001 |
| Specificity (%) | 98.8 (98.7; 98.8) | 99.0 (98.9; 99.2) | 98.8 (98.7; 98.9) | 98.6 (98.4; 98.7) | 98.4 (98.0; 98.7) | <0.001 |
| PPV (%) | 30.8 (28.6; 33.0) | 28.7 (23.8; 34.0) | 33.6 (30.3; 37.1) | 29.3 (25.6; 33.4) | 25.6 (18.8; 33.7) | 0.35 |
FP false positive examinations, BC breast cancers, PPV positive predictive value. BC/1000 = (Screen-detected cancers/1000) + (Interval cancers/1000), Sensitivity of screening = screen-detected cancers/(screen-detected cancers + interval cancers), Specificity = true negative examinations/(true negative examinations + false positive examinations), PPV = screen-detected cancers/(screen-detected cancers + false positive examinations)