de Blay F, Zana H, Offner M, Verot A, Velten M, Pauli G
Hôpital Civil, Hôpitaux Universitaires de Strasbourg, France.
J Allergy Clin Immunol. 1993 Aug;92(2):255-63. doi: 10.1016/0091-6749(93)90169-g.
The objectives of this study were to demonstrate the usefulness of Receiver Operating Characteristic (ROC) analysis in the definition of a positive threshold in the comparison of two in vitro tests for detecting IgE antibodies and to determine the clinical relevance of specific IgE tests according to the sensitivity and specificity determined by ROC analysis.
Specific IgE levels were compared with the use of both MATRIX (Abbott Laboratories, Chicago, Ill.) and PHADEZYM (Pharmacia, Uppsala, Sweden) tests in 109 patients: 86 allergic patients and 23 control subjects. All allergic patients had a clinical history of allergy to mite, cat, grass pollen, or birch pollen and positive skin prick test results to the suspected allergen. Using various levels of specific IgE, we determined the points of the ROC curves with the best ratio of true positives to false positives for four aeroallergens (i.e., mite, cat, grass pollen, and birch pollen).
Except for mite allergen there was no correspondence between the positive threshold values determined by ROC analysis with MATRIX and PHADEZYM tests. In terms of class, when ROC analysis was used, the threshold was class III with the MATRIX test and class II with PHADEZYM test for cat, grass pollen, and birch pollen and class III for mite. According to the threshold value, sensitivity and specificity for MATRIX and PHADEZYM tests were similar except for cat, for which the PHADEZYM test had a lower sensitivity (0.71) than the MATRIX test (0.90). With mite allergen the predictive value of only one positive MATRIX test result was 0.96. The specificities of MATRIX and PHADEZYM tests were 100% in both nonatopic and atopic control groups.
We conclude that ROC analysis is a reliable method for comparing IgE in vitro tests and that it emphasizes the lack of correspondence between arbitrary units given for each in vitro test. ROC analysis appears to be a good method for helping to standardize IgE in vitro tests.
本研究的目的是证明受试者工作特征（ROC）分析在为两种检测IgE抗体的体外试验比较定义阳性阈值时的有用性，并根据ROC分析确定的敏感性和特异性来确定特异性IgE检测的临床相关性。
在109例患者中使用MATRIX（雅培实验室，伊利诺伊州芝加哥）和PHADEZYM（法玛西亚，瑞典乌普萨拉）试验比较特异性IgE水平：86例过敏患者和23例对照受试者。所有过敏患者均有对螨、猫、草花粉或桦树花粉过敏的临床病史，且对疑似过敏原的皮肤点刺试验结果为阳性。使用不同水平的特异性IgE，我们确定了四种气传变应原（即螨、猫、草花粉和桦树花粉）的ROC曲线中真阳性与假阳性比例最佳的点。
除螨变应原外，MATRIX和PHADEZYM试验通过ROC分析确定的阳性阈值之间没有对应关系。就类别而言，使用ROC分析时，对于猫、草花粉和桦树花粉，MATRIX试验的阈值为III类，PHADEZYM试验的阈值为II类，螨的阈值为III类。根据阈值，MATRIX和PHADEZYM试验的敏感性和特异性相似，但猫除外，对于猫，PHADEZYM试验的敏感性（0.71）低于MATRIX试验（0.90）。对于螨变应原，仅一个阳性MATRIX试验结果的预测值为0.96。MATRIX和PHADEZYM试验在非特应性和特应性对照组中的特异性均为100%。
我们得出结论，ROC分析是比较IgE体外试验的可靠方法，并且它强调了每种体外试验给出的任意单位之间缺乏对应关系。ROC分析似乎是有助于使IgE体外试验标准化的好方法。
