Table A1.
Sensitivity and specificity with 95% confidence interval for detecting lame cows (locomotion score ≥2) the number of observations on farm 1 (n = 3006), and on farm 2 (n = 1119).
| IPS Indicators Present | Sensitivity | Specificity | PPV | NPV |
|---|---|---|---|---|
| SW | 46.2 (35.8–56.9) | 93.4 (92.5–94.3) | 18.4 (14.8–22.6) | 98.2 (97.8–98.5) |
| AWD | 44.1 (33.8–54.8) | 92.6 (91.6–93.5) | 16.0 (12.7–19.8) | 98.1 (97.7–98.4) |
| SHH | 76.3 (66.4–84.5) | 97.5 (96.8–98.0) | 49.0 (42.7–55.2) | 99.2 (98.9–99.5) |
| OH | 38.7 (28.8–49.4) | 87.0 (85.7–88.2) | 8.7 (6.7–11.1) | 97.8 (97.4–98.1) |
| One or more (≥1) | 100.0 (96.1–100.0) | 71.8 (70.1–73.4) | 10.2 (9.7–10.7) | 100.0 |
| Two or more (≥2) | 92.5 (85.1–96.9) | 98.6 (98.1–99.0) | 68.3 (61.1–74.6) | 99.8 (99.5–99.9) |
| Three (3) | 11.8 (6.1–20.2) | 100.0 (99.9–100.0) | 100.0 | 97.3 (97.1–97.5) |
| SW | 32.5 (18.6–49.1) | 95.0 (93.5–96.2) | 19.4 (12.6–28.8) | 97.4 (96.8–97.9) |
| AWD | 55.0 (38.5–70.7) | 93.2 (91.6–94.7) | 23.2 (17.4–30.1) | 98.2 (97.5–98.7) |
| SHH | 77.5 (61.6–89.2) | 96.3 (95.0–97.3) | 43.7 (35.4–52.3) | 99.1 (98.5–99.5) |
| OH | 52.5 (36.1–68.5) | 80.0 (77.5–82.3) | 8.9 (6.6–11.8) | 97.9 (97.0–98.4) |
| One or more (≥1) | 100.0 (91.2–100.0) | 66.1 (63.2–68.9) | 9.9 (9.1–10.6) | 100.0 |
| Two or more (≥2) | 95.0 (83.1–99.4) | 98.4 (97.5–99.1) | 69.1 (58.1–78.3) | 99.8 (99.3–99.9) |
| Three (3) | 22.5 (10.8–38.5) | 100.0 (99.7–100.0) | 100.0 | 97.2 (96.7–97.6) |
SW = shifting weight, AWD = abnormal weight distribution, SHH = swollen heel or hock joint, OH = overgrown hoof, LS = locomotion score, PPV = positive predictive value, NPV = negative predictive value, Total-denotes the number of observed indicators.