Death certificates in epidemiological studies, including occupational hazards: inaccuracies in occupational categories

Our plain-English summary of Death certificates in epidemiological studies, including occupational hazards: inaccuracies in occupational categories, by I.J. Selikoff (American Journal of Industrial Medicine, 1992).

The study

• Author: I.J. Selikoff
• Journal: American Journal of Industrial Medicine
• Published: 1992;22(4):493-504
• Cited by: 16 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

We compared death certificates for asbestos-associated diseases (mesothelioma, lung cancer, asbestosis) in two asbestos workers' cohorts. One (insulation workers) had current or recent employment and a strong, continuing union support system which gave them much information about the effects of asbestos exposure. The second cohort, asbestos factory workers, had no such advantage. The factory had closed almost 30 years before, and its workers had dispersed into many areas of the state and nation. Accuracy of medical diagnosis was comparable in the two groups, but occupational listings were not. Three-quarters of the insulators' death certificates told of asbestos work, while virtually none of the factory workers' certificates provided such information, even for deaths of mesothelioma and asbestosis. The data indicate that disease categories, based on medical and pathological diagnoses, at least for asbestos-associated disease, tend to be accurate. Attempts to identify groups at risk by sorting occupational categories can give variable results, good for those with current exposures, much less satisfactory for those with long-past occupational exposures.

In plain English

This study compared death certificates with 'best evidence' causes of death, which were based on review of all available medical and pathology material, in two groups of asbestos-exposed men. The first group was the 17,800 members of the insulation workers' union in the United States and Canada on January 1, 1967. Of them, 4,951 died from 1967 to 1986, including 458 from mesothelioma (173 pleural, 285 peritoneal). The second group was 933 men employed between 1941 and 1945 at a New Jersey amosite asbestos products factory that closed in 1954. The author examined 198 of their deaths from lung cancer, mesothelioma and asbestosis. Only 39.5% of the insulators' mesothelioma deaths were correctly categorized on their certificates. For the factory workers, certificates agreed with best evidence for 82.4% of lung cancer, 58.8% of mesothelioma and 48.9% of asbestosis deaths. Among the 458 insulators who died of mesothelioma, about three-quarters of death certificates recorded asbestos or insulation work. Only six of the 198 factory workers' certificates (3.0%) gave any evidence of asbestos. The author concluded that disease categories tended to be accurate for asbestos disease, but occupation listings were much less satisfactory for long-past exposures.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Comparison of death certificate entries (cause of death and occupation) with best-evidence cause of death in two prospectively followed cohorts of asbestos-exposed workers
• Who was studied: Two cohorts. (1) All 17,800 men in the Insulation Workers' Union in the United States and Canada on January 1, 1967, of whom 4,951 died from 1967 to 1986; 458 died of mesothelioma. (2) 933 workers employed at a New Jersey asbestos (amosite) products factory from June 15, 1941 to December 31, 1945, of whom 740 died from 1941 to 1990; 198 consecutive deaths from lung cancer (136), mesothelioma (17) and asbestosis (45) were studied.
• Exposure: Asbestos insulation work (current or recent employment) in the union cohort; work at an amosite asbestos products factory in New Jersey (1941 to 1954, often short-term) in the factory cohort
• Main results:
  • Insulation workers: of 458 mesothelioma deaths, 173 were pleural and 285 peritoneal
  • Insulation workers: only 89 pleural and 92 peritoneal mesotheliomas were appropriately categorized on death certificates (39.5%)
  • Insulation workers: the occupation analysis covered the death certificates of the 458 insulators who died of mesothelioma (Table II).
  • Insulation workers: occupations on those certificates were mostly accurate and showed asbestos exposure, with asbestos insulation work found on about three-quarters of them.
  • Insulation workers who died of mesothelioma but had other diagnoses on the certificate: the occupation listed did not appear to vary substantially
  • Factory workers: death certificate diagnoses were relatively accurate compared with best evidence. Lung cancer was correctly recorded in 112 of 136 deaths (82.4%) and mesothelioma in 10 of 17 (58.8%) (Table IV).
  • Factory workers: asbestosis was correctly recorded on 22 of 45 asbestosis death certificates (48.9%)
  • Factory workers: only six of 198 death certificates (3.0%) gave some evidence that asbestos was involved (best evidence: 1 lung cancer, 2 mesothelioma, 3 asbestosis)
  • Factory workers: among the 16 men who had worked 10 or more years in the plant, occupations on death certificates were marginally more accurate
• The authors' conclusion: The author concluded that death certificate disease categories, at least for asbestos, tend to be accurate. Identifying groups at risk by sorting occupational categories gives variable results: good for people with current exposures, much less satisfactory for people with long-past exposures.

Topics

The National Library of Medicine indexes this study under subjects our site covers: Asbestosis.

Medical terms in this study, explained in our Lexicon: Death Certificate, Mesothelioma, Lung Cancer, Insulator, Asbestos Exposure, Occupational Exposure.

Related studies

• Use of death certificates in epidemiological studies, including occupational hazards: variations in discordance of different asbestos-associated diseases on best evidence ascertainment — I.J. Selikoff, H. Seidman (1992)
• Influence of age at death on accuracy of death certificate disease diagnosis: findings in 475 consecutive deaths of mesothelioma among asbestos insulation workers and asbestos factory workers — I.J. Selikoff (1992)
• Estimation of the incidence of pleural mesothelioma according to death certificates in France — Y. Iwatsubo, M. Matrat, et al. (2002)
• Recovering missing mesothelioma deaths in death certificates using hospital records — V.S. Santana, E. Algranti, et al. (2018)
• Risk of stomach cancer associated with 12 workplace hazards: analysis of death certificates from 24 states of the United States with the aid of job exposure matrices — P. Cocco, M.H. Ward, et al. (1999)
• Validation of death certificates in asbestos workers — M.L. Newhouse, J.C. Wagner (1969)

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