An economical enzymatic assay for HDL phosphatidyl choline is described, as adapted for the Cobas-Bio analyser (Hoffmann LaRoche). This method entails the enzymatic cleavage of phosphatidyl choline by phospholipase C from B. cereus, hydrolysis of phosphoryl choline and enzymatic determination of choline with choline oxidase by an enzymatic colour test. This method provides consistent values and is, by comparison to the enzymatic UV method (assaying choline with choline kinase in an optical test procedure), simpler to perform, more precise, and less expensive.