Methodology in industrial health studies: Social Security disability data and the medical care system

This paper is directed at the exploration and development of the Social Security data, in the ascertainment and evaluation of industrial health effects. The focus of the study is on disability data, as a national uniform means to identify illnesses and disease that occurred prior to death, that were not recorded on the death certificates. A cohort of employees of an industrial company was processed through the Social Security System to simultaneously identify the disability and death claims that were filed. The total number of white males that filed disability claims was 1,333 and for white females 278. The total number of claims filed for the white males was 1,734 and for white females 382. Comparisons were made of all causes of disability with all causes of death for white males and white females. A remarkably high percentage of causes of disability were not recorded or available by death certificate for ICD categories of diseases and specific cancer sites. The study also demonstrated that disability data contribute significantly to the confirmation of the diagnosis for the cancer sites. The development of the methodology linking Social Security data on disability, medical care, and mortality with industrial medical and environmental exposure data in epidemiological studies is discussed.