title: Applicability of various quality-control sera to assay of high-density lipoprotein cholesterol.
abstract: Effective internal quality control and external quality assessment of high-density lipoprotein cholesterol assay is made difficult by analyte instability, and the suitability of quality-control sera for this purpose has not been studied. We have therefore investigated the properties of 25 different control sera from 15 suppliers by estimating within-batch precision for the two precipitation procedures used most widely (phosphotungstate/Mg2+ and heparin/Mn2+ with enzymic measurement of cholesterol. Some sera had properties similar to those of fresh human serum, but others demonstrated poor precision for one or both procedures or contained apparent high-density lipoprotein cholesterol in unphysiological concentrations. A study of six sera indicated that between-batch precision was consistent with the within-batch findings. We found that eight of the 25 batches of quality-control serum we investigated may be used for internal quality control and external quality assessment of high-density lipoprotein cholesterol assay.
mesh_terms: D011232:Chemical Precipitation; D002784:Cholesterol / Q000097:blood*; D006493:Heparin; D006801:Humans; D007202:Indicators and Reagents; D008075:Lipoproteins, HDL / Q000097:blood*; D008274:Magnesium; D008345:Manganese; D008722:Methods; D010772:Phosphotungstic Acid; D011786:Quality Control; D012015:Reference Standards; D012016:Reference Values
chemical_list: D007202:Indicators and Reagents; D008075:Lipoproteins, HDL; D010772:Phosphotungstic Acid; D008345:Manganese; D006493:Heparin; D002784:Cholesterol; D008274:Magnesium