Survey of total error of precipitation and homogeneous HDL-cholesterol methods and simultaneous evaluation of lyophilized saccharose-containing candidate reference materials for HDL-cholesterol

Background: Standardization of HDL-cholesterol is needed for risk assessmen t. We assessed for the first time the accuracy of HDL-cholesterol testing i n The Netherlands and evaluated 11 candidate reference materials (CRMs), Methods: The total error (TE) of HDL-cholesterol measurements was assessed in native human sera by 25 Dutch clinical chemistry laboratories, Concomita ntly, the suitability of lyophilized, saccharose-containing CRMs (n = 11) f or HDL-cholesterol was evaluated. Results: In the precipitation method group, which included 25 laboratories and four methods, the mean (minimum-maximum) TE was 11.5% (2.7-25.2%), sign ifying that 18 of 25 laboratories satisfied the TE goal of less than or equ al to 13% issued by the National Cholesterol Education Program (NCEP). In t he homogeneous HDL-cholesterol method group, which included five laboratori es, each performing two different methods, the mean (minimum-maximum) TE wa s 9.5% (6.6-17.3%) for the Boehringer assay and 15.7% (3.3-30.7%) for the G enzyme assay. For the Boehringer homogeneous assay, one of five laboratorie s did not meet the TE criterion, whereas far the Genzyme homogeneous assay, three of five laboratories exceeded the 13% criterion. The biases on the H DL-cholesterol values found by various precipitation methods were highly va riable in all CRMs, irrespective of the quality, whereas the biases found b y the homogeneous method from Boehringer were far less than +/-5% for the h ighest-quality CRMs (CRMs 4-6). Conclusions: The NCEP goal was met by 24 of 35 laboratories assessed by use of native human sera. Selectively pooled, lyophilized CRMs that are cryopr otected with 200 g/L saccharose have ample potential for use in the standar dization of homogeneous HDL-cholesterol methods. (C) 1999 American Associat ion for Clinical Chemistry.