Evaluation of false positive and false negative outcomes in NTP long-term rodent carcinogenicity studies.

: The decision-making process used by the National Toxicology Program (NTP) in its evaluation of long-term rodent carcinogenicity studies was investigated to determine whether or not this procedure resulted in an excessive number of false positive or false negative outcomes. All site-specific tumor incidences that were found to be significantly (p 90%) for this target site.