Estimating the probability of occurrence of tumor for a rare cancer with zero occurrence in a sample

Regul Toxicol Pharmacol. 1996 Apr;23(2):139-44. doi: 10.1006/rtph.1996.0035.


In many physical situations one needs to estimate the probability of occurrence of a rare event based on a random sample when the event has not occurred at all. For example, if the true lifetime incidence of a tumor at a particular tissue site is less than 1%, it is not uncommon to observe no tumors in a typical sample size of 50 animals. This paper explores the suitability of nonzero Bayesian estimation procedures to replace zero maximum likelihood estimates for tissue sites with nonzero background tumor incidences.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Review

MeSH terms

  • Animals
  • Bayes Theorem*
  • Dose-Response Relationship, Drug
  • Incidence
  • Lethal Dose 50
  • Male
  • Neoplasms, Experimental / epidemiology*
  • Rats
  • United States
  • United States Food and Drug Administration