ABSTRACT
The purpose of studies of occupational epidemiology is to investigate the existence and nature of the associations between exposure to physical and chemical agents and outcomes such as morbidity and mortality. While it is very difficult, and some may claim it is impossible, to prove causality between exposure and disease in the occupational setting, the validity of associations observed in epidemiologic studies is determined by estimating the probability that the observed associations could be due to chance alone. The degree to which this causal association can be established is, in part, determined by the quality of the industrial hygiene data which are used to describe the exposure characteristics of the study population. There are many factors and criteria which are used to assess the validity of causal associations in epidemiologic studies; Table 1 summarizes some commonly used examples [1], Most of the factors imply a measurement of exposure or dose, at least qualitatively. This presentation discusses a model which may be used to visualize the components of the exposure-response relationship, with some examples of the use of industrial hygiene data in studies of occupational epidemiology. The model is illustrated in Figure 1, and the first portion of the presentation will describe the components of the model, the measurement techniques applicable to each component, and the factors which mediate the pathways between the components. Evaluation Criteria in Epidemiologic Studies. https://www.niso.org/standards/z39-96/ns/oasis-exchange/table">
Strong association of the factor (e.g., chemical exposure) to the outcome.
A dose-response relationship between the factor and the outcome.
A clear temporal relationship between the factor and the outcome.
A biologically plausible explanation for the observed association.
A consistency of findings across studies.
Source: based on Lilienfeld, A. M., and D. E. Lilienfeld. Foundations of Epidemiology (New York: Oxford University Press, 1980).
Conceptual model of causal association in occupational epidemiology. https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780367810870/47191a23-74c2-4c65-89b4-d42d302a0f39/content/fig20_1.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/>