A simulation study comparing different experimental designs for estimating uptake and elimination rates.
The design of ecotoxicological studies requires decisions about the number and spacing of exposure groups tested, the number of replications, the spacing of sampling times, the duration of the study, and other considerations. For example, geometric spacing of sampling times or toxicant concentrations is often used as a default design. Optimal design methods in statistics can suggest alternative spacing of sampling times that yield more precise estimates of regression coefficients. In this study, we use a computer simulation to explore the impact of the spacing of sampling times and other factors on the estimation of uptake and elimination rate constants in an experiment addressing the bioaccumulation of a contaminant. Careful selection of sampling times can result in smaller standard errors for the parameter estimates, thereby allowing the construction of smaller, more precise confidence intervals. Thus, the effort invested in constructing an optimal experimental design may result in more precise inference or in a reduction of replications in an experimental design.
Bell
Bryan R
BR
Center for Environmental Toxicology and Statistics, Miami University, Oxford, Ohio 45056, USA. bbell@jumpstartpoa.biz
Bailer
A John
AJ
Wright
Stephen E
SE
D000818:Animals; D003198:Computer Simulation; D004785:Environmental Pollutants / Q000378:metabolism*; D008954:Models, Biological; D017711:Nonlinear Dynamics; D010599:Pharmacokinetics; D012044:Regression Analysis; D012107:Research Design
D004785:Environmental Pollutants