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Controversy in the allometric application of fixed- versus varying-exponent models: a statistical and mathematical
Huadong Tang1, Azher Hussain, Mauricio Leal
1Drug Metabolism and Pharmacokinetics, Merck Research Laboratory, Kenilworth, New Jersey 07033, USA. huadong.tang@spcorp.com
Abstract:
This commentary is a reply to a recent article by Mahmood commenting on the authors' article on the use of fixed-exponent allometry in predicting human clearance. The commentary discusses eight issues that are related to criticisms made in Mahmood's article and examines the controversies (fixed-exponent vs. varying-exponent allometry) from the perspective of statistics and mathematics. The key conclusion is that any allometric method, which is to establish a power function based on a limited number of animal species and to extrapolate the resulting power function to human values (varying-exponent allometry), is infused with fundamental statistical errors.
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