Application of a job-exposure matrix to a case-control study of lung cancer

Interview information was obtained on primary and secondary occupations for 261 male lung cancer patients and 444 controls residing on the island of Oahu, HI. With the use of a computerized job-exposure matrix (JEM), exposure levels were assigned to each subject for each of 5 known and 2 likely lung carcinogens. A multiple logistic regression model was used to compute the odds ratio (OR) for exposure to each carcinogen, adjusted for age, ethnicity, and pack-years of smoking. On the basis of the criterion of either a dose-response effect or a statistically significant OR (P less than .05) or both, 5 of the 7 carcinogens (4 of the 5 known carcinogens) were found to be associated with lung cancer risk. However, on the basis of the single criterion of a significant OR, only 3 of the 7 carcinogens (2 of the 5 known carcinogens) were associated with lung cancer risk. Due to its relative insensitivity, this JEM may have limited usefulness in the identification of exposure-disease relationships and should not be applied uncritically.