Documentation of Biomarkers in the 2006 and 2008 Health and Retirement Study

Biomarkers refer to the general range of physiological, metabolic, biochemical, endocrine and genetic measures that can be obtained in living organisms. The term is most commonly used to refer to one-time biochemical or hematological measures made on blood or other available bodily fluids, but perhaps the term should be used for a broader range of measures. In 2006 and 2008, HRS included the following biomarkers measurements, administered in this order: Saliva collection for DNA extraction; Blood spot collection for cholesterol, hemoglobin A1C, CRP and cystatin C analysis (results for C-reactive protein and cystatin C are forthcoming). This report describes the following for each of the measures listed above: Rationale and key citations; Sample description; Measure description; Equipment; Protocol description; Special instructions.