Table 2:
Sensitivities and PPVs of Different Deep Learning SSDs at a 50% Confidence Threshold for Different Metastasis Sizes
| All Metastases | Metastases <3 mm | Metastases ≥3 mm to < 6 mm | Metastases ≥6 mm | |||||
|---|---|---|---|---|---|---|---|---|
| Technique | Sensitivity (%) | PPV (%) | Sensitivity (%) | PPV (%) | Sensitivity (%) | PPV (%) | Sensitivity (%) | PPV (%) |
| Baseline SSD | 81 (80, 82) [190/234] | 36 (35, 37) [190/530] | 15 (12, 18) [3/20] | 100 (100, 100) [3/3] | 70 (68, 72) [57/82] | 35 (32, 38) [57/161] | 98 (97, 99) [130/132] | 36 (35, 37) [130/366] |
| SSD plus ResNet50 | 73 (72, 74) [171/234] | 29 (28, 30) [171/581] | 10 (7,13) [2/20] | 100 (100, 100) [2/2] | 55 (53, 57) [45/82] | 34 (31, 37) [45/134] | 94 (93, 95) [124/132] | 28 (26, 30) [124/445] |
| SSD plus focal loss | 77 (76, 78) [180/234] | 26 (26, 26) [180/681] | 20 (14, 26) [4/20] | 80 (64, 96) [4/5] | 62 (60, 64) [51/82] | 21 (19, 23) [51/248] | 95 (94, 96) [125/132] | 29 (28, 30) [125/428] |
| RetinaNet | 79 (77, 81) [184/234] | 13 (12, 14) [184/1412] | 40 (33, 47) [8/20] | 2 (1, 3) [8/410] | 66 (61, 71) [54/82] | 9 (8,10) [54/573] | 92 (91, 93) [122/132] | 28 (27, 29) [122/429] |
Note.—Numbers in parentheses are 95% confidence intervals, and numbers in brackets are raw data. The baseline SSD achieved the highest metastasis-wise sensitivity and PPV. PPV = positive predictive value, SSD = single-shot detector.