SHOULD OCCUPATIONAL CODES BE OBTAINED FROM CENSUS-DATA OR FROM RETROSPECTIVE SURVEY DATA IN STUDIES ON OCCUPATIONAL-HEALTH

The aim of this study was to assess the quality of occupational history information obtained via retrospective interview questions by comparison with occupational information for the same individuals obtained via a number of censuses. Moreover, morbidity patterns were investigated for different occupational exposure categories that were constructed either on occupational data gathered retrospectively or on data gathered longitudinally through censuses. The study population consisted of 6764 men and 2104 women who were interviewed within the Swedish Survey on Living Conditions. Census data on occupation from 1960, 1970 and 1975 were used for comparison. There was high level of agreement between the two data bases for occupational categories containing workers who were stable in their occupations. The correspondence was better for women. Prevalence rates for different long-term illnesses were almost the same for the categories, no matter which of the data bases was used for constructing the categories. Thus, we have found that self-reported work histories might be a useful way of controlling for occupational exposures in the past. © 1990 Kluwer Academic Publishers.