EXPOSURE ASSESSMENT IN INDUSTRY SPECIFIC RETROSPECTIVE OCCUPATIONAL EPIDEMIOLOGY STUDIES

Quantitative estimation of exposure for occupational epidemiology stud ies has received increasing attention in recent years and, as a result , a body of methodological literature has begun to take form. This pap er reviews the generic issues in the methodology of exposure assessmen t, particularly methods for quantitative retrospective assessment stud ies. A simple framework, termed an exposure data matrix (EDM), for def ining and analysing exposure data is proposed and discussed in terms o f the definition of matrix dimensions and scales. Several methods for estimation, interpolation, and extrapolation, ranging from subjective ratings to quantitative statistical modelling are presented and discus sed. The various approaches to exposure assessment based on the EDM co ncept are illustrated with studies of lung disease among coal miners a nd other dust and chemically induced chronic occupational diseases. Th e advantages of validated statistical models are emphasised. The impor tance of analysis and control of errors in exposure assessments, and i ntegration of the exposure assessment and exposure-response processes, especially for emerging occupational health issues, is emphasised.