Molecular epidemiology: principles and practices. Schulte PA, Perera FP, eds., San Diego, CA: Academic Press, 1993 Apr; :159-198
Molecular epidemiology does not differ in purpose from epidemiology in general, thaI is, the study of the distribution and determinants of healthrelated states and events in populations, and the application of this study to the control of health problems (Last, 1988). Further, molecular epidemiologic studies generally are based on dassic epidemiologic designs. What makes molecular epidemiology distinctive, as discussed in Chapter 1, is its abiliry to look inside the "black box" of the exposure-disease continuum. In the process, it may reduce misclassification of exposure, provide insight into underlying mechanisms, identify gene-gene and gene-environment interactions, and provide information when intervention is potentially more effective. This chapter considers how biomarkers can be used in the major epidemiologic study designs. We first review the biomarker categories that represent the continuum from exposure to disease. We then explore the initial methodologic work necessary to characterize a newly developed biomarker before it is applied in etiologic and intervention studies. Hulka (1991) has defined these as transitional studies that bridge the gap from the laboratory to population-based srudies of disease. We then consider the applicadon of biomarkers to case control, prospective, and screening and intervention studies. Finally, we present examples of various biological markers in epidemiologic study designs.