1. The 53 rd Annual Meeting of the Japan Diabetes Society Nationwide Surveillance Study on Hemoglobin A1C by JDS in 2009 Katsuhiko Kuwa 1, Masao Umemoto 2, Izumi Takei 3, Atsunori Kashiwagi 4 National Metrology Institute of Japan 1, Reference Material Institute for Clinical Chemistry Standards 2, Tokyo Dental College Ichikawa General Hospital 3, Shiga University of Medical Science 4 S1-4

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

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

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

5. Procedures Cycle 1 Sample Delivery → Measurement → Reporting Cycle 2 Sample Delivery → Measurement → Reporting Cycle 3 Sample Delivery → Measurement → Reporting Cycle 4 Sample Delivery → Measurement → Reporting Cycle 5 Sample Delivery → Measurement → Reporting 293 Routine Laboratories 4 Samples S1-1 ～ S1-4 289 Routine Laboratories 4 Samples S3-1 ～ S3-4 282 Routine Laboratories 4 Samples S2-1 ～ S2-4 16 Manufacturers 10 Samples S1-1 ～ S1-3, S2-1 ～ S2-3, S3-1 ～ S3-3, S4-4 4 Reference Laboratories 13 Samples S1-1 ～ S1-4, S2-1 ～ S2-4, S3-1 ～ S3-4, S4-4 Analysis of Reporting Data Value Assingnment

6. Target Values of PT Samples in RLs

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

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

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

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

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

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

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

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

15. Conclusions 1.JDS performed the proficiency testing of HbA1c measurement for confirming the commutability in Japan. 2. Total 888 laboratories participated in this proficiency testing. 3.The mean CV was confirmed less than 3.0 % against JDS number from 5.2 % to 10.8 %. 4.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. 5.The commutability of inter-methods for measurement were maintained at the same degree against the former proficiency testing in 2003.