General Information on Laboratory Tests and Biomarkers

Laboratory biomarkers, often referred to simply as biomarkers, are measurable indicators used to evaluate various biological processes, conditions, or diseases in a laboratory setting. These biomarkers are found in various body fluids (such as blood, urine, and others) or tissues and provide valuable information for screening, diagnosis, prognosis, and monitoring of many medical conditions. Biomarkers are also valuable for research to understand disease mechanisms and develop new treatments. Nevertheless, it is important to interpret test results in the context of the patient’s overall clinical picture, as elevated or abnormal biomarker levels do not always indicate disease and vice versa. This chapter therefore reviews some fundamental aspects for understanding the underlying biological basis and optimizing the clinical utility of laboratory biomarkers.