Methods to Story on Asbestos Job Exposure, Peritoneum Cancer and Gender Methods Section of Article Includes Data on Peritoneum and Gender

METHODS

Since 1984, the National Cancer Institute, the National Institute for Occupational Safety and Health, and the National Center for Health Statistics have supported the coding of occupation and industry titles on death certificates from a number of U.S. states according to the 1980 U.S. Census occupation and industry codes [Burnett and Dosemeci, 1994]. Briefly, it currently consists of a total of 4.5 million death certificates from 24 U.S. states, covering the years 1984–1992. Only one occupation and industry combination is reported for every subject, and no duration of employment is available. Data reported on the death certificates of subjects aged 20 years or more were used to evaluate the risk of peritoneal cancer associated with occupational exposure to asbestos by gender. Cases were 657 subjects (249 men and 408 women) who died from cancer of the peritoneum (ICD-9 codes 158.8 and 158.9).

Eighteen men and 20 women were African-American. Because of even smaller numbers, subjects of Asian origin and Native Americans were excluded from the analysis. All the remaining were noted as Whites in the death certificate. Ten controls per case were selected from among subjects who died from non-malignant diseases, frequency-matched to cases by geographic region, race, gender, and 5-year age group.

Risk of peritoneal cancer was first explored by industry and occupation. To evaluate risk in relation to occupational exposure to asbestos, we designed a job-exposure matrix based on the 1980 U.S. Census list of occupations and industries, and subsequently applied it to the occupation and industry codes in the death certificates of cases and controls.