Validation of work histories for the purpose of epidemiological studies.
Bond GG; Bodner KM; Olsen GW; Burchfiel CM; Cook RR
Appl Occup Environ Hyg 1991 Jun; 6(6):521-527
A discussion was presented of strengths, limitations and validation of employer records and interviews as primary information sources for work histories in occupational epidemiologic studies. Misclassification of exposure could be nondifferential or differential. The former occurred independent of disease and usually underestimated exposure response relationships. Differential misclassification was not independent and could produce underestimates and overestimates of risk. Industry based studies generally used employer or union records for work history information. Advantages included independence from disease events, enhanced accuracy, greater precision in job and department titles and complete chronological job history. Disadvantages were that records could be missing, information was pertinent only to that employer, implied precision could be greater than actual precision and generic job titles were sometimes used. Interviews of subjects or surrogates were generally used in community based studies. Advantages included flexibility to tailor data collection to relevant hypotheses, ability to explore individual work practices and opportunity to assess subjective signs or symptoms of exposure. Disadvantages included human memory fallibility and recall or interviewer bias due to lack of independence from disease events. Methods for enhancing validity of work history data were suggested, including focusing on longer term employees in an occupation or industry and obtaining work history data from multiple sources. Use of biological markers for validating work history exposures was noted. The authors conclude that it is necessary that investigators validate exposure estimates and adjust risk estimates appropriately for misclassification bias.
NIOSH-Publication; NIOSH-Contract; NIOSH-Contract; Contract-91-38661; Humans; Industrial-hygiene; Epidemiology; Occupational-exposure; Exposure-levels; Work-analysis; Information-systems
Applied Occupational and Environmental Hygiene