Validation of work histories obtained from interviews.

There have been few attempts to assess the validity of occupational histories obtained from interviews. A nested case-control study of lung cancer conducted in 1985 among a cohort of 19,608 male workers at a Texas chemical production facility provided such an opportunity. Telephone interviews were attempted with 308 lung cancer patients and 588 matched controls or their next of kin in order to gather information on tobacco use, diet, places of residence, and occupations. Interview data from 734 respondents (143 subjects and 591 next of kin) were then compared with the records of work area assignments maintained by the company and with exposure profiles developed by an industrial hygienist. Respondents recalled 48.4 per cent of all documented work area assignments, but only 2.6 per cent of the chemical agents judged as likely exposures. Recall of usual work area assignment was 70.8 per cent. Among the factors found to have most influenced recall were the number and durations of assignments, a subjective assessment of the quality of the interview, and the relationship of the interview respondent to the subject. The elapsed time from job assignment to interview was also found to affect recall of the longest assignment of the subject.