“Conversely, the release of elements or cell lysis associated with the coagulation cascade is responsible for the increase in potassium (±6%), inorganic phosphate (±11%), ammonia (±38%), and lactate (±22%) in serum compared to plasma [9]. Furthermore, anticoagulants, preservatives, and other additives that aid or inhibit coagulation may interfere with the assay, as discussed later. Also, the presence of fibrinogen may interfere with chromatic detection or binding in immunoassays or the appearance of a peak that may simulate a false monoclonal protein in the gamma region during protein electrophoresis [9,10]. Serum Versus Plasma for Clinical Laboratory Tests There are many advantages to using plasma over serum for clinical laboratory analysis. However, for some analytes, serum is preferred over plasma. These issues are addressed in this section.”