Volume 13, Number 3—March 2007
Research
Risk for Infection with Highly Pathogenic Influenza A Virus (H5N1) in Chickens, Hong Kong, 2002
Table 4
Comparison of different multivariate models of risk factors for avian influenza type A virus (H5N1) infection among chicken farms, Hong Kong, 2002**
| Variable | Category | OR (95% CI) | ||
|---|---|---|---|---|
| Model A | Model B | Model C | ||
| 1 | Owner lives off farm | 37.04 (3.18–431.63) | 12.64 (1.18–135.35) | 45.84 (3.65–575.69) |
| 2 | Sell to retail markets | 20.11 (1.47–274.98) | 30.26 (2.26–405.09) | 28.39 (2.30–350.40) |
| 3 | Highest death rate >30 d | 17.37 (1.03–292.01) | 20.51 (1.51–277.96) | 24.28 (1.62–364.87) |
| 4 | Wild birds in feed trough | 0.07 (0.01–0.85) | ||
| 5 | Chicken count | 1.07 (1.01–1.12) | ||
| 6 | Relative in poultry industry | 19.41 (1.46–257.74) | ||
| Cox and Snell R2 | 0.42 | 0.46 | 0.43 | |
| Nagelkerke R2 | 0.63 | 0.68 | 0.65 | |
| Significance of Hosmer and Lemeshow test | 0.91 | 0.67 | 0.82 | |
| Degrees of freedom | 3 | 8 | 3 | |
*OR, odds ratio; CI, confidence interval.


