title: Relation between statistics and treatment-related changes obtained from toxicity studies in rats: if detected a significant difference in low or middle dose for quantitative values, this change is considered as incidental change?
abstract: The purpose of a toxicity test is to determine the no-observed-effect level (NOEL) of test substance through biological and pharmacological techniques. If the low dose not does show statistically significant and biologically relevant changes in the data evaluated in a study, the usual practice is to consider this dose as the NOEL. To overcome this, 6 types of techniques that seemed to be appropriate are presented in this paper by investigating the results of several domestic and foreign theses on toxicology. The most appropriate techniques appear to be the trend test, comparison between treatment group and historical control by t-test, and confirmation that all individual values lie within the 95% confidence interval (2 SD) of the historical control value, if a significant difference is admitted in the low dose.
authors.affiliation: Chemical Management Center, National Institute of Technology and Evaluation, Tokyo. kobayashi-katsumi@nite.go.jp
authors.forename: Katsumi
authors.initials: K
authors.lastname: Kobayashi
authors.forename: Yuki
authors.initials: Y
authors.lastname: Sakuratani
authors.forename: Takemaru
authors.initials: T
authors.lastname: Abe
authors.forename: Satoshi
authors.initials: S
authors.lastname: Nishikawa
authors.forename: Jun
authors.initials: J
authors.lastname: Yamada
authors.forename: Akihiko
authors.initials: A
authors.lastname: Hirose
authors.forename: Eiichi
authors.initials: E
authors.lastname: Kamata
authors.forename: Makoto
authors.initials: M
authors.lastname: Hayashi
mesh_terms: D000818:Animals; D015197:Carcinogenicity Tests / Q000379:methods / Q000706:statistics & numerical data*; D003627:Data Interpretation, Statistical; D004305:Dose-Response Relationship, Drug; D019055:No-Observed-Adverse-Effect Level; D051381:Rats