International Inventory of Occupational Exposure Information: OMEGA-NET

Exposure assessment is a cornerstone in occupational epidemiology—one of the key methodological considerations—and not without its challenges. The goal in any study is to derive an accurate, precise, and biologically relevant exposure estimate for each worker under study (Nieuwenhuijsen, 2003). Without high-quality exposure assessment, the power of a study to detect an association between exposure and health outcome is diminished, which may bias results and lead to spurious interpretations. Study to study differences in exposure assessment quality are more apparent when drawing the evidence together. As has been shown in examples on benzene (Vlaanderen et al., 2008), asbestos (Lenters et al., 2011), and trichloroethylene (Purdue et al., 2011), heterogeneity in findings across epidemiological studies are at least partly explained by variations in the quality of exposure assessment.