title: National Survey on Internal Quality Control for HbA(1c) Analytical Instruments in 331 Hospital Laboratories of China.
abstract: BACKGROUND
  The narrow gap of HbA1 value of mass fraction between "normal" (< 6.0%) and "diabetes" (≥ 6.5%) necessitates tight control of inter-assay standardization, assay precision, and trueness. This survey was initiated to obtain knowledge of the current situation of internal quality control (IQC) practice for HbA(1c) in China and find out the most appropriate quality specifications.
  
  
  METHODS
  Data of IQC for HbA(1c) in 331 institutions participating in the national proficiency testing (PT) programs in China were evaluated using four levels of quality specifications, and the percentages of laboratories meeting the quality requirement were calculated to find out the most appropriate quality specifications for control materials of HbA(1c) in China.
  
  
  RESULTS
  The IQC data varied vastly among 331 clinical laboratories in China. The measurement of control materials covered a wide range from 4.52% to 12.24% (inter-quartile range) and there were significant differences among the CVs of different methods, including LPLC, CE-HPLC, AC-HPLC, immunoturbidimetry, and others. Among the four main methods, CE-HPLC and AC-HPLC achieved a better precision.
  
  
  CONCLUSIONS
  As we can see, the performance of laboratories for HbA(1c) has yet to be improved. Clinical laboratories in China should improve their performance with a stricter imprecision criteria.
authors.forename: Rong
authors.initials: R
authors.lastname: Zeng
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Haijian
authors.initials: H
authors.lastname: Zhao
authors.forename: Yang
authors.initials: Y
authors.lastname: Fei
authors.forename: Zhiguo
authors.initials: Z
authors.lastname: Wang
mesh_terms: D001774:Blood Chemical Analysis / Q000592:standards / Q000706:statistics & numerical data; D002681:China; D006442:Glycated Hemoglobin / Q000032:analysis*; D007755:Laboratories, Hospital / Q000706:statistics & numerical data*; D011786:Quality Control
chemical_list: D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human