Table 1. Performance characteristics in the evaluation of the study images for the first (white light endoscopic imaging only) and second (chromoendoscopy-aided) readings.
| a) Overall image evaluation | ||||
| Observer | Accuracy with WLI only, % | Accuracy with chromoendoscopy, % | Improvement in accuracy, % [95 % CI] | P value |
| 1 | 48.7 | 62.0 | 13.3 [7.5, 19.0] | < 0.001* |
| 2 | 59.0 | 76.0 | 17 [10.1, 23.6] | < 0.001* |
| 3 | 48.0 | 76.2 | 28.2 [21.7, 34.3] | < 0.001* |
| 4 | 59.0 | 66.7 | 7.7 [3.6, 11.7] | < 0.001* |
| Globally | 53.7 | 70.2 | 16.5 [13.6, 19.4] | < 0.001 * |
| b) True ulcerative image evaluation | ||||
| Observer | Accuracy with WLI only, % | Accuracy with chromoendoscopy, % | Improvement in accuracy, % [95 % CI] | P value |
| 1 | 40.8 | 59.2 | 18.4 [12.0, 24.5] | < 0.001* |
| 2 | 58.4 | 82.4 | 24 [17.0, 30.7] | < 0.001* |
| 3 | 42.3 | 77.8 | 35.5 [28.4, 41.9] | < 0.001* |
| 4 | 56.0 | 66.4 | 10.4 [5.9, 14.8] | < 0.001* |
| Globally | 49.4 | 71.4 | 22 [18.9, 25.1] | < 0.001 * |
| c) False ulcerative image evaluation | ||||
| Observer | Accuracy with WLI only, % | Accuracy with chromoendoscopy, % | Decrease in accuracy (%) [95 % CI] | P value |
| 1 | 88 | 76 | 12 [– 0.6, 23.6] | 0.109 |
| 2 | 62 | 44 | 18 [– 1.3, 35.9] | 0.108 |
| 3 | 76 | 68 | 8 [– 4.6, 20.0] | 0.344 |
| 4 | 74 | 68 | 6 [– 3.3, 14.9] | 0.375 |
| Globally | 75 | 64 | 11 [4.1, 17.7] | 0.003 * |
WLI, white light imaging; CI, confidence interval.
*
Statistically significant.