Application of a method to evaluate the quality of work histories and document the exposure assessment process

Review of work history records by industrial hygienists is an important component of many occupational epidemiologic studies. A number of factors may influence the hygienist, such as the quality of the data and his or her previous experience. As part of a case-control study of mesothelioma, a system was developed to capture data on several factors that can be considered in a review of work history information.

The overall quality of the work history record was described by noting the completeness and the consistency of the information; for any potential exposures, the reviewer experience on which the decision was based and the relative quality of the information were categorized. Because of the potential for mesothelioma cases and their next-of-kin to have undergone rigorous questioning about previous asbestos exposure an evaluation of the knowledge of the respondent was included. The frequency and intensity of exposure were also evaluated.

Evaluation of 3,444 work records is described. The importance of data completeness in the overall evaluation of quality is shown; follow-up questions regarding specific work tasks provide information not elicited in the standard interview process. The use of the literature was an important resource to the reviewer. Asbestos was reported by the respondent as an exposure on 149 work records; of these, 111 (74%) were judged to represent an unusual level of knowledge for a next-of-kin respondent.

The approach presented allows capture of information about data quality and experience of the reviewer in an epidemiologic analysis. The ratings of frequency and intensity of exposure allow exploration of differences in exposure-response analyses using various exposure metrics.