15903 IUPAC Gold Book - multistage model 10.1351/goldbook.15903 15903 current 1 Dose–response model for cancer death estimation of the form \[P = 1 - \exp [-(q_{0} + q_{1}d_{1} + q_{2}d_{2} + \ldots + q_{k}d_{k})]\] where \(P\) is the probability of cancer death from a continuous dose rate, \(d_{i}\) , of group (or stage) \(i = 0, 1, 2 \ldots\), the \(q\)’s are constants, and \(k\) is the number of dose groups (or, if less than the number of dose groups, \(k\) is the number of biological stages believed to be required in the carcinogenesis process). With the multistage model, it is assumed that cancer is initiated by cell mutations in a finite series of steps. PAC, 2007, 79, 1153. 'Glossary of terms used in toxicology, 2nd edition (IUPAC Recommendations 2007)' on page 1267 (https://doi.org/10.1351/pac200779071153) https://goldbook.iupac.org/terms/view/15903/html https://goldbook.iupac.org/terms/view/15903/json https://goldbook.iupac.org/terms/view/15903/plain Citation: 'multistage model' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.15903 The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms. If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org . The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using. 2026-05-31T01:07:16+00:00