Schmidt R M, Brosious E M
Am J Clin Pathol. 1979 May;71(5):534-9. doi: 10.1093/ajcp/71.5.534.
In the 1976 hemoglobinopathy proficiency testing survey of the Center for Disease Control (CDC), whole-blood samples from hematologically normal adults and from individuals heterozygous for beta-thalassemia were shipped to survey participants. The object of this survey was to determine the state of the art for technics used to quantitate hemoglobin A2 (Hb A2) and to test the ability of laboratories to differentiate between blood samples having normal Hb A2 levels and those having elevated levels (i.e., those from individuals with beta-thalassemia trait). The results of Hb A2 quantitation obtained from 183 volunteer participant laboratories were compared with those obtained from 24 reference laboratories. Individual values varied greatly among laboratories and among methods for both normal and elevated Hb A2 samples. The results returned by many laboratories were not within 2 SD of the reference laboratory mean and also were not sufficiently accurate to differentiate between the normal blood samples and those with beta-thalassemia trait. The results suggest that methods for quantitating Hb A2 need to be standardized and a suitable method for determining laboratory performance found.
在疾病控制中心（CDC）1976年的血红蛋白病能力验证调查中，将血液学正常成年人以及β地中海贫血杂合子个体的全血样本运送给参与调查者。本次调查的目的是确定用于定量血红蛋白A2（Hb A2）的技术的当前水平，并测试各实验室区分Hb A2水平正常的血样和水平升高的血样（即来自具有β地中海贫血特征个体的血样）的能力。将183个志愿参与的实验室获得的Hb A2定量结果与24个参考实验室获得的结果进行了比较。无论是正常Hb A2样本还是升高的Hb A2样本，各实验室之间以及各方法之间的个体值差异都很大。许多实验室返回的结果不在参考实验室均值的2个标准差范围内，也不够准确，无法区分正常血样和具有β地中海贫血特征的血样。结果表明，需要对Hb A2定量方法进行标准化，并找到一种合适的方法来确定实验室性能。
