Predictor | Odds ratio (95% C.I.) | χ^{2} | df | P |
---|---|---|---|---|
Base model covariates | ||||
Trial area | 253.49 | 8* | <0.001 | |
Gender | 36.86 | 1 | <0.001 | |
Male vs. female | 1.54 (1.34–1.76) | |||
Tooth wear | 18.31 | 5 | 0.003 | |
2 vs. 1 | 0.98 (0.54–1.78) | |||
3 vs. 1 | 1.24 (0.69–2.23) | |||
4 vs. 1 | 1.21 (0.67–2.19) | |||
5 vs. 1 | 1.64 (0.89–3.01) | |||
Not recorded vs. 1 | 0.45 (0.11–1.85) | |||
Carcass storage | 3.86 | 1 | 0.050 | |
>7 days vs. ≤7 days | 0.64 (0.41–1.01) | |||
Necropsy laboratory | 26.69 | 9 | <0.001 | |
Culture laboratory | 1.55 | 2 | 0.460 | |
Cull sequence 1 | 0.727 | 1 | 0.394 | |
Cull sequence 2 | 52.61 | 1 | <0.001 | |
Interannual variation | ||||
FMD | 18.19 | 1 | <0.001 | |
2002 vs. other years | 1.70 (1.33–2.16) | |||
Boundary permeability | ||||
Permeability × cull sequence-1 interaction ^{†} | 3.16 | 1 | 0.076 | |
Permeability × cull sequence-2 interaction ^{†} | 14.99 | 1 | <0.001 | |
Capture location within trial area | ||||
Capture location ^{†} | 9.49 | 1 | 0.002 | |
Capture location × cull sequence-1 interaction ^{†} | 6.58 | 1 | 0.010 |
C.I., confidence interval.
↵*The variable representing 10 trial areas is associated with only eight degrees of freedom because inclusion of the boundary permeability variable (a characteristic of each trial area) accounted for one of the trial area degrees of freedom.
↵ ^{†}Odds ratios associated with the cull sequence variables and their interaction terms are in Fig. 2. Fitted values are in Fig. 1d.