Biomarkers are directly-measured biological indicators of disease, health, exposures, or other biological information. In population and social sciences, biomarkers need to be easy to obtain, transport, and analyze. Dried Blood Spots meet this need, and can be collected in the field with high response rates. These elements are particularly important in longitudinal study designs including interventions where attrition is critical to avoid, and high response rates improve the interpretation of results. Dried Blood Spot sample collection is simple, quick, relatively painless, less invasive then venipuncture, and requires minimal field storage requirements (i.e. samples do not need to be immediately frozen and can be stored for a long period of time in a stable freezer environment before assay). The samples can be analyzed for a variety of different analytes, including cholesterol, C-reactive protein, glycosylated hemoglobin, numerous cytokines, and other analytes, as well as provide genetic material. DBS collection is depicted as employed in several recent studies.
Biomarkers are extremely useful tools across multiple disciplines, including medicine, cell biology, genetics, psychology, sociology, demography, and social epidemiology. Within each discipline, early phase validity and reliability biomarker research was used to uncover both hidden disease risk and provide longitudinal prediction of health outcomes. In these instances, biomarkers that are accurate, durable (i.e. they can survive the lag between sample collection and implementation of the lab assay to extract the biomarker), and versatile (i.e. useful in a variety of models) are required.