Numerous studies have shown that elevated low-density lipoproteins (LDL) is a major cause of coronary heart disease (CHD). In addition, recent clinical trials have shown that LDL-lowering therapy reduces risk for CHD. For these reasons, the Adult Treatment Panel (ATP) III of the National Cholesterol Education Program (NCEP) identifies LDL as the primary target of cholesterol-lowering therapy. The Denka Seiken Direct LDL assay accurately measures LDL in the specimen using a two step procedure using patented technology. In the first step, non-LDL lipoproteins, including chylomicrons, VLDL, IDL and HDL, are decomposed by cholesterol esterase and cholesterol oxidase. The hydrogen peroxides produced are finally decomposed by the action of catalase. In the second step, an LDL-specific surfactant is used to release the cholesterol and similar enzymatic degradation in the presence of peroxidase to produce a measurable purple-red color on any clinical chemistry analyzer.