Abstract
Most studies on the half-lives of environmental contaminants have been based on small sample sizes and a limited number of repeated measurements. In this paper, we address issues of study design and sample size for half-life studies. Useful guidelines are provided for choosing the number of repeats and the optimal time interval between repeats for estimating an individual's half-life with a given level of precision, while minimizing the cost of the study. In addition, sample size and power considerations for studies comparing two population half-lives are investigated. An example is presented using data from a study on polychlorinated biphenyls and breast cancer.
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Kim, M.Y., Dubin, N. Study design and sample size considerations for half-life studies. Arch. Environ. Contam. Toxicol. 30, 423–429 (1996). https://doi.org/10.1007/BF00212304
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DOI: https://doi.org/10.1007/BF00212304