Volume 13, Number 6—June 2007
Research
Bovine Spongiform Encephalopathy and Spatial Analysis of the Feed Industry
Table
Estimations of regression parameters of the disease mapping model with covariates meat-and-bone meal and animal fat*
Model | Estimations of β | Prediction interval | Odds ratio† | |
---|---|---|---|---|
0 | DIC = 1596 | |||
1 | ΔDIC = -5.0 | [–1.243, –0.116] | ||
[ 0.091, 2.562], p = 0.017 | 3.8 | |||
2 | ΔDIC = –1.0 | [–0.8 , 0.131] | ||
[–0.674, 2.230], p = 0.145 | n.s. | |||
3 | ΔDIC = –3.0 | [–1.315, -0.094] | ||
[ 0.01, 2.686], p = 0.035 | 3.7 | |||
[–1.456, 1.683], p = 0.438 | n.s. |
*λi,parameter of the Poisson distribution for area i; ei expected number of bovine spongiform encephalopathy cases for area i; β, set of regression parameters to link the relative risk to the covariates; ui, spatial component of smoothing for area i; MBM, meat-and-bone meal; FAT, animal fat; n.s., not significant. Variations of the deviance information criterion (ΔDIC) were calculated in comparison with the DIC value of model 0. The 95% prediction intervals were based on the quantiles of the Markov Chain Monte Carlo sample.
†Odds ratio was computed as exp(β); it compares the bovine spongiform encephalopathy risk for a 100% difference in the use of MBM in the area.