ABSTRACT
Biomarkers are directly measured traits that provide insight into the functioning of biological systems. They often involve the collection and subsequent analysis of biological specimens such as blood, saliva, and urine. Biomarkers also include physical and functional measures such as blood pressure and actigraphy (i.e., assessment of human rest/activity cycles). Biomarkers provide valuable information about biological processes ranging from normal to pathogenic that may contribute clinically identifiable disease.
