Table 1 Relationship between the proportion of positive piglets in a 56-crate farrowing room and the true and apparent (by FOF) proportion of positive litters assuming a clustering level of 0.61
Proportion of PRRSV-positive individual piglets (%) | True proportion of PRRSV-positive litters (upper and lower 95% quantiles) (%) | Apparent proportion of PRRSV-positive litters by FOF (upper and lower 95% quantiles) (%) |
|---|---|---|
1 | 5.36 (1.79, 7.14) | 2.06 (1.07, 3.53) |
5 | 8.93 (7.14, 12.50) | 6.48 (5.30, 8.58) |
10 | 14.29 (10.71, 17.86) | 11.25 (9.31, 13.92) |
15 | 19.64 (16.07, 23.21) | 16.35 (14.47, 19.21) |
20 | 23.21 (21.43, 26.79) | 21.60 (18.73, 24.19) |
25 | 28.57 (25.00, 32.14) | 26.66 (23.50, 29.31) |
30 | 33.93 (30.36, 37.50) | 31.35 (28.77, 34.33) |
35 | 39.29 (35.71, 42.86) | 36.16 (33.49, 39.44) |
40 | 44.64 (41.07, 48.21) | 41.30 (38.05, 44.71) |
45 | 48.21 (44.64, 53.57) | 46.54 (43.10, 49.68) |
50 | 53.57 (50.00, 57.14) | 51.56 (48.34, 54.58) |