Clin Chem. 1987 Dec;33(12):2267-71.
A method for measuring glycated hemoglobin (Hb A1c) and an accompanying method of specimen transport to a central laboratory were developed for the multicenter Diabetes Control and Complications Trial (DCCT). In the DCCT, results for Hb A1c are used to assess chronic glycemic control for data collection and patient management. During the feasibility phase of the trial, central (CHL) and backup laboratories using automated, "high-performance" ion-exchange liquid-chromatographic methods were established. Whole-blood samples were stored (4 degrees C) at each of the 21 clinical centers for up to 72 h before air-express shipment to the CHL. Quality-control procedures included daily analyses of three calibration specimens. A pooled hemolysate was assayed frequently over time as a long-term quality control (LTQC). After 18 months, within- and between-run CVs were less than 6%. Mean values for split duplicate samples assayed in a masked fashion at the CHL were nearly identical. LTQC results indicated no significant assay drift over time. More than 6000 samples were assayed (mean interval between obtaining the blood sample and completing the assay: less than six days). Hb A1c evidently can be precisely and reliably measured in the context of a long-term, multicenter trial such as the DCCT.
针对多中心糖尿病控制与并发症试验（DCCT），开发了一种测量糖化血红蛋白（Hb A1c）的方法以及一种将样本运送至中心实验室的配套方法。在DCCT中，Hb A1c的检测结果用于评估慢性血糖控制情况，以进行数据收集和患者管理。在试验的可行性阶段，设立了使用自动化“高性能”离子交换液相色谱法的中心实验室（CHL）和备用实验室。全血样本在21个临床中心的每个中心于4℃保存长达72小时，然后通过航空快递运往CHL。质量控制程序包括每日对三个校准样本进行分析。随着时间的推移，经常对混合溶血产物进行检测，作为长期质量控制（LTQC）。18个月后，批内和批间变异系数均小于6%。在CHL以盲法检测的分割重复样本的平均值几乎相同。LTQC结果表明，随着时间的推移，检测没有明显漂移。共检测了6000多个样本（从采集血样到完成检测的平均间隔时间：少于6天）。在诸如DCCT这样的长期多中心试验中，Hb A1c显然能够被精确且可靠地测量。
