Katan M B, van der Haar F, Kromhout D, Schouten F J
Clin Chem. 1982 Apr;28(4 Pt 1):683-6.
Serum cholesterol concentrations of subjects in epidemiological studies were measured after direct addition of Liebermann-Burchard reagent; results were calibrated with human serum pools assayed according to Abell et al. (J. Biol. Chem. 195:357-366, 1952). Accuracy and precision were monitored for six years by analysis of internal-control pools and blind external-control pools. For various internal-control pools, the imprecision (CV) of the long-term averages of run means ranged from 0.5 to 0.9%. The within-run CV for internal control and patients' sera was about 1%. For blind control sera with different concentrations (provided by the Centers for Disease Control, Atlanta, GA, over the same period), the average difference per three-month period between the values found and the target values was usually between -0.5% and +0.7% for medium-concentration pools and between -2% and +2% for low- and high-concentration pools (extreme values: -2.4% and +2.5%). The CV per three-month period ranged from 0.6 to 2.7%. Sera from subjects on diets of high or low linoleic acid content were analyzed to study the effect of the fatty acid portion of serum cholesterol esters; the differences between values obtained with the comparison method and the direct method was insignificant on both diets. We conclude that the use of serum calibrators eliminates the bias inherent in the direct method.
在直接添加利伯曼-布赫ard试剂后，对流行病学研究中受试者的血清胆固醇浓度进行了测量；结果用人血清混合液进行校准，该混合液是按照阿贝尔等人（《生物化学杂志》195卷：357 - 366页，1952年）的方法测定的。通过分析内控混合液和盲法外部对照混合液，对准确性和精密度进行了六年的监测。对于各种内控混合液，运行均值长期平均值的不精密度（CV）范围为0.5%至0.9%。内控和患者血清的批内CV约为1%。对于不同浓度的盲法对照血清（由佐治亚州亚特兰大疾病控制中心同期提供），中浓度混合液每三个月测得的值与目标值之间的平均差异通常在 - 0.5%至 + 0.7%之间，低浓度和高浓度混合液则在 - 2%至 + 2%之间（极值： - 2.4%和 + 2.5%）。每三个月的CV范围为0.6%至2.7%。对食用高亚油酸或低亚油酸含量饮食的受试者的血清进行分析，以研究血清胆固醇酯脂肪酸部分的影响；在两种饮食中，比较法和直接法获得的值之间的差异均不显著。我们得出结论，使用血清校准物消除了直接法中固有的偏差。
