Table 3.
Sensitivity and specificity using a ≥5% and ≥10 % weight loss threshold at Year 1 based upon several weight loss thresholds at Months 1 and 2
| Month | Weight loss threshold | Sensitivity or true positive rate (N) | Specificity or true negative rate (N) | False negative rate (N) | False positive rate (N) |
|---|---|---|---|---|---|
| Using a ≥5% weight loss threshold at Year 1 | |||||
| 1 | 2% | 57.9% (405) | 77.8% (1260) | 42.1% (294) | 22.2% (359) |
| 1 | 3% | 81.0% (566) | 55.1% (892) | 19.0% (133) | 44.9% (727) |
| 1 | 4% | 92.6% (647) | 32.0% (518) | 7.4% (52) | 68.0% (1101) |
| 2 | 3% | 59.4% (409) | 85.1% (1374) | 40.6% (280) | 14.9% (240) |
| 2 | 5% | 86.5% (596) | 57.9% (935) | 13.5% (93) | 42.1% (679) |
| 2 | 7% | 97.7% (673) | 28.6% (461) | 2.3% (16) | 71.4% (1153) |
| Using a ≥10% weight loss threshold at Year 1 | |||||
| 1 | 2% | 45.5% (648) | 87.0% (779) | 54.5% (775) | 13.0% (116) |
| 1 | 3% | 70.3% (1001) | 67.4% (603) | 29.7% (422) | 32.6% (292) |
| 1 | 4% | 86.5% (1231) | 42.2% (378) | 13.5% (192) | 57.8% (517) |
| 2 | 3% | 42.2% (596) | 94.1% (839) | 57.8% (815) | 5.9% (53) |
| 2 | 5% | 73.6% (1039) | 73.5% (656) | 26.4% (372) | 26.5% (236) |
| 2 | 7% | 93.2% (1315) | 42.7% (381) | 6.8% (96) | 57.3% (511) |
Sensitivity rate is defined as the percentage of participants failing to achieve ≥5 or ≥10% weight loss at Year 1 who are correctly identified using the initial weight loss threshold [true positives/(true positives + false negatives)], while false negative rate is the percentage of those incorrectly identified [false negatives/(true positives + false negatives)]. Specificity rate is defined as the percentage of participants achieving a ≥5% or ≥10% weight loss at Year 1 who are correctly identified using the initial weight loss threshold [true negatives/(true negatives + false positives)], while false positive rate is the percentage of those incorrectly identified [false positives/(true negatives + false positives)].