Model uncertainty and model averaging in the estimation of infectious doses for microbial pathogens.
Food-borne infection is caused by intake of foods or beverages contaminated with microbial pathogens. Dose-response modeling is used to estimate exposure levels of pathogens associated with specific risks of infection or illness. When a single dose-response model is used and confidence limits on infectious doses are calculated, only data uncertainty is captured. We propose a method to estimate the lower confidence limit on an infectious dose by including model uncertainty and separating it from data uncertainty. The infectious dose is estimated by a weighted average of effective dose estimates from a set of dose-response models via a Kullback information criterion. The confidence interval for the infectious dose is constructed by the delta method, where data uncertainty is addressed by a bootstrap method. To evaluate the actual coverage probabilities of the lower confidence limit, a Monte Carlo simulation study is conducted under sublinear, linear, and superlinear dose-response shapes that can be commonly found in real data sets. Our model-averaging method achieves coverage close to nominal in almost all cases, thus providing a useful and efficient tool for accurate calculation of lower confidence limits on infectious doses.
Department of Mathematics and Statistics, California State University, Long Beach, CA 90840-1001, USA. hojin.moon@csulb.edu
Hojin
H
Moon
Steven B
SB
Kim
James J
JJ
Chen
Nysia I
NI
George
Ralph L
RL
Kodell
D000818:Animals; D001499:Bayes Theorem; D008962:Models, Theoretical; D009010:Monte Carlo Method; D051381:Rats; D035501:Uncertainty