title: Economical LD50 and slope determinations.
abstract: Many regulatory standards and guidelines required LD50 determinations and dose-response curve slopes, using at least 5 animals per sex per dosage level and at least 3 levels. In contrast, the current trend is to use as few animals as necessary for toxicological studies. The moving average method for calculation of the LD50 has been available since 1947 but, as it does not involve curve fitting, has not been used to determine the slope. An accurate adaptation of this is presented so that both the LD50 and slope can be determined using very few animals and using levels with 0 or 100% kills; not usable with probit determinations.
mesh_terms: D000818:Animals; D004305:Dose-Response Relationship, Drug; D005260:Female; D007928:Lethal Dose 50; D008297:Male; D014116:Toxicology / Q000379:methods*