The 53 rd Annual Meeting of the Japan Diabetes Society

1. The 53 rd Annual Meeting of the Japan Diabetes Society S1-4 Nationwide Surveillance Study on Hemoglobin A1C by JDS in 2009 Katsuhiko Kuwa1, Masao Umemoto2, Izumi Takei3, Atsunori Kashiwagi4 National Metrology Institute of Japan1, Reference Material Institute for Clinical Chemistry Standards2, Tokyo Dental College Ichikawa General Hospital3, Shiga University of Medical Science4

2. Global Harmonization in HbA1c Measurement Mono-S(%) NGSP(%) NGSP(%) NGSP(%) JDS(%) IFCC(mmol/mol）　NGSP(%)

3. Reference System for HbA1c in Japan MaterialCalibrationProcedureImplementation Value assignment SI Primary calibrator IFCC(mmol/mol) IFCC-Network※ IFCCreference method Reference standard (JDS Lot4) IFCC(mmol/mol) IFCC derived-JDS(%) JSCC-Network※ JSCC/JDSdesignated comparison method (KO500) Working standard IFCC(mmol/mol) HbA1c(%), JDS(%) JSCC RMLs Manufacturer’s standing measurement procedure Manufacturer’s product calibrator＊ Manufacturer Routine measurement procedure Routine samples End-user ※ Maintenance of ME ＊HbA1c・JDS・IFCC values Result＊

4. Total Participating Laboratories: 888 Routine Laboratories : 864 Enzymatic Assay 9 % Reference Laboratories 4 Manufacturers 16 Immunoassay 27 % Routine Clinical Laboratories 754 HPLC 64 % Participating Laboratory and Method in 2009 JDS Proficiency Testing

5. Procedures 16 Manufacturers10 Samples S1-1～S1-3, S2-1～S2-3, S3-1～S3-3, S4-4 Cycle 1 Sample Delivery →　Measurement →　Reporting 293 Routine Laboratories4 Samples S1-1～S1-4 Cycle 4 Sample Delivery →　Measurement →　Reporting Cycle 2 Sample Delivery →　Measurement →　Reporting 4 Reference Laboratories13 Samples S1-1～S1-4, S2-1～S2-4, S3-1～S3-4, S4-4 282 Routine Laboratories4 Samples S2-1～S2-4 Cycle 5 Sample Delivery →　Measurement →　Reporting Cycle 3 Sample Delivery →　Measurement →　Reporting Value Assingnment 289 Routine Laboratories4 Samples S3-1～S3-4 Analysis of Reporting Data

6. Target Values of PT Samples in RLs

7. T.V. 10.59 (%) T.V. 5.17 (%) T.V. 5.34 (%) T.V. 6.88(%) Histograms of Measured Values（1） Cycle 1 ： S1-1～S1-4

8. T.V. 5.84(%) T.V. 9.79 (%) T.V. 7.40(%) T.V. 5.45 (%) Histograms of Measured Values（2） Cycle 2 ： S2-1～S2-4

9. T.V. 5.47(%) T.V. 10.18 (%) T.V. 6.69(%) T.V. 5.47 (%) Histograms of Measured Values（3） Cycle 3 ： S3-1～S3-4

10. Comparison of CVs in Each Procedure Cycle The mean CV(%) was obtained less than 3.0 % in all Samples. Procedure Cycle in Routine Laboratory

11. Cycle 1 S1 S2 S3 S4 ＋SD ◆ Mean T.V. －SD Method Method Comparison Study（1）

12. Cycle 2 S1 S2 S3 S4 ＋SD ◆ Mean T.V. －SD Method Method Comparison Study（2）

13. Cycle 3 S1 S2 S3 S4 ＋SD ◆ Mean T.V. －SD Method Method Comparison Study（3）

14. Accuracy Grading Based on Target Values Set by the DCM(KO500) Fulfillment Rate（%） The 92 % of participating laboratories were allowed within ±5 % of relative bias against the target values. The 92 % of participating laboratories were satisfied within ±5 % of relative bias against the target values. 97.1 % 100 91.6 % S1(%) 91.6 % 80 S2(%) 60 7.4 % S3(%) 40 S4(%) 20 Mean(%) 0 Within±5 % Within±7 % Within±7 % Within±5 % % % % % 0 0 0 0 . . . . 5 7 以上 3 10 % ± ± ± 1 ± . ～ ～ 10 % % ～ 1 1 % . . 1 ± 3 5 . 7 ± ± Relative Bias(%) ± Relative Bias(%)

15. Conclusions • JDS performed the proficiency testing of HbA1c measurement for confirming the commutability in Japan. • 2. Total 888 laboratories participated in this proficiency testing. • The mean CV was confirmed less than 3.0 % against JDS number from 5.2 % to 10.8 %. • The 92 % and 97 % of participating laboratories were allowed within ±5 % and ±7 % of relative bias against the accuracy grading based on target values set by designated comparison method(KO500 HPLC), respectively. • The commutability of inter-methods for measurement were maintained atthe same degree against the former proficiency testing in 2003.