Environ Toxicol Chem. 2022 Feb 13. doi: 10.1002/etc.5306. Online ahead of print.
ABSTRACT
Tests for dose-response trend may be used to support conclusions on the toxicity of a substance in a range of doses evaluated in a comparative experiment. Criteria are proposed for evaluating and comparing alternative tests, and applied in a comparison of some tests applicable with continuous responses, namely a multiplicity-adjusted pairwise comparison procedure, a trend test based on a single contrast, and four multiple-contrast trend tests. Methods considered treat dose as ordinal information. A particular focus is comparison of the simple test of a single contrast, with coefficients proportional to dose rank, to multiple-contrast methods available with modern computing. To explore the role of dose-response curve shape, we generate regular dose response shapes (or profiles), defined by mean response for each dose level, using a simple grid-based algorithm. Power for individual profiles may be used to illustrate the effect of curve shape on the power of alternative tests. To facilitate selection of tests we report average power over profiles, averaging at different levels of granularity, first separately for each of several curve shape categories, then over all profiles weighting shape categories equally. Power results for the six tests evaluated provide at least clear distinctions between some procedures that are more-preferred, versus less-preferred. Our analyses expand the comparisons of tests available and contribute methodology for choice of statistical methods for toxicological data analysis. This article is protected by copyright. All rights reserved. © 2022 SETAC.
PMID:35156237 | DOI:10.1002/etc.5306
