Decision rule approach applied to estimate occupational lead exposure in a case-control study of kidney cancer.

Background: We developed a systematic, data-driven approach to estimate metrics of occupational exposure to lead to aid in epidemiologic analyses in a case-control study of kidney cancer.

Methods: Probability of exposure to ten lead sources was assigned using decision rules developed from an extensive literature review and expert judgement. For jobs with >50% probability of exposure, we assigned source-specific frequency based on subjects' self-reported task frequencies or means of subjects' job-groups and source-specific intensity estimates of blood lead (μg/dL).

Results: In our study, 18.7% of employed person-years were associated with high (≥80%) probability of exposure to any lead source. The most common medium (>50%) or high probability source of lead exposure was leaded gasoline (2.5% and 11.5% of employed person-years, respectively). The median blood lead attributed to occupational exposure was 3.1 μg/dL.

Conclusions: These rules can aid in future studies after population-specific adaption for geographic differences and different exposure scenarios.