The epidemiology of cancer in Oklahoma: examination of Cramer's hypothesis.

Abstract

Cancer epidemiology was studied from mortality data using age-specific and age-adjusted rates by sex and county of residence for 1956 to 1960 and 1961 to 1965. Geographic and time variations were examined as well as sex ratios and proportionate death rates. Age-adjusted rates for two time periods were used to examine Cramer's hypothesis which states that host susceptibility to cancer is predetermined and external factors determine the site of cancer occurrence. Elevation in total cancer mortality occurred in the urban northeast geographic area, reflecting perhaps the high rates for specific sites such as lung and cervix. Variations with time appeared for the different systems and the sex subgroups but not for total cancer. This finding is consistent with Cramer's hypothesis. Additional findings show an increase in susceptibility of men to cancer over women for most sites, and a proportionate death rate of about 33.4%, 23.2%, 16.1%, and 10.3% respectively for the gastrointestinal, reproductive, respiratory, and hematopoietic systems. Analysis of the data was limited to the white population.