" EXTERNAL QUALITY EVALUATION PROGRAM FOR POCT GLUCOSE TESTING years of experience

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1 Commissie voor Klinische Biologie Commission de Biologie Clinique " EXTERNAL QUALITY EVALUATION PROGRAM FOR POCT GLUCOSE TESTING 8 3 years of experience CM Van Campenhout JC Libeer WIV/ISP/IPH Clinical Biology Brussels - BELGIUM

2 Glucose testing has evolved from primitive urine tasting and chemical tests to sophisticated enzymatic and biosensor technologies with computerized data recording capabilities. Glucose monitoring will become more important in the future, as the incidence of diabetes increases. Current meters allow for the rapid analysis of small amounts of blood in a variety of healthcare settings, but suffer from the instability and common interferences of their enzyme-based technologies.. Future research promises to develop less invasive and more continuous monitoring methods... The history, advantages and limitations of point-of-care testing for blood glucose. LabMed..3, June Published Online: 1//5

3 GLUCOSE METERS ARE WIDELY SPREAD IN HOSPITAL SETTINGS In Belgium: EQA became mandatory started in Regulation for set-up of POCT in hospitals announced in 7 by Commission of Clinical Biology.

4 I. DESING OF THE EQA SCHEME Testing model Samples Participants II. GLUCOSE METERS / PERFORMANCES Precision Bias Over-All performances III. PROBLEMS concerning POCT Glucose EQA Program IV. CONCLUSIONS

5 TESTING MODEL SURVEY ORGANISED IN COOPERATION WITH EUROTROL (The Netherlands) Web-Based program STATISTICS ARE PERFORMED REAL TIME AT CLOSING DATE DIFFERENT KINDS OF REPORTS ARE AVAILABLE (tailor made) IN THE BELGIAN EQA SCHEME -8, 1 SAMPLES WERE DISTRIBUTED * 7*

6 SAMPLES SAMPLES ARE FROM HEALTHY SUBJECTS (blood donors) PREPARED THE DAY OF SAMPLING / SHIPPING (Sanquin The Netherlands) ADDITION OF GLYCOLYSIS INHIBITOR (??) GLUCOSE CONCENTRATION IS ADJUSTED FINAL GLUCOSE CONCENTRATION IS DETERMINED WITH THE REFERENCE METHOD Hexokinase method VALUE

7 Monday morning SAMPLES

8 Monday morning

9 Monday morning

10 Monday morning

11 Monday morning Commissie voor Klinische Biologie Commission de Biologie Clinique Tuesday morning Over 3 samples have to be prepared to sent to about Belgian laboratories all over the country.

12 Tuesday until Friday Laboratories REF. LABORATORIES Target setting

13 Results 7

14 NUMBER OF PARTICIPANTS _ NUMBER OF GLUCOSE METERS > PARTICIPATING HOSPITALS WERE REGISTERED THE NUMBER OF SAMPELS SENT TO THE PARTICIPANTS EQUALIZES THEIR NUMBER OF GLUCOSE METERS PRESENT IN THE HOSPITAL SETTING SURVEY Participants Nb of results

15 GLUCOSE METERS / PERFORMANCES 39 DIFFERENT MODELS ARE INVOLVED 3 SYSTEMS WITH POSSIBILITIES FOR WHOLE BLOOD / OR PLASMA CALIBRATION A MAXIMUM OF 8 DIFFERENT MODELS OF GLUCOSE METERS ARE OBSERVED IN ONE INSTITUTION THE TOTAL AMOUNT OF GLUCOSE METERS PER SITE VARIED FROM WITH A MEAN OF 7 METERS PER SITE

16 1 1 1 NUMBER OF METERS PER INSTITUTE SURVEY I Median = 19 Mean = Frequency NUMBER OF METERS

17 1 1 1 NUMBER OF METERS PER INSTITUTE SURVEY 8 IV Median = 19 Mean = 5 Frequency NUMBER OF METERS

18 9 5 Rapidpoint 5 Rapidlab 85 Rapidlab 15 NUMBER Of RESULTS PER TYPE OF GLUCOSE METER in the BELGIAN HOSPITALS Precision Xtra Precision Xceed Precision PCX One Touch Ultra/One Touch Ultra One Touch Ultra Smart One Touch Profile One Touch II One Touch Basic Glucose 1/1+ (whole blood) Glucocard X meter Glucocard Memory PC Glucocard Memory Glucocard Memory Glucocard Gluco Touch GEM 3 Freestyle Lite Freestyle Freedom Freestyle Elite XL Elite Ascensia Contour (whole blood) Ascensia Contour (plasma) Aeroset Accutrend Sensor Accutrend Accu-Chek Sensor (whole blood) Accu-Chek Sensor (plasma) Accu-Chek Inform (whole blood) Accu-Chek Inform (plasma) Accu-Chek Aviva 13 9 Accu-Chek Inform II (plasma) ABL POCT I vs. 8 POCT IV >>

19 SURVEY ASSESSMENT RESULTS ARE COMPARED TO THE CONCENTRATION STATED BY THE REFERENCE METHODE HEXOKINASE -CV < 5% - Computer flagging results for bias : BIAS INTERPRETATION Criteria TE 1% Excellent ADA : < 5% > 1% and 15% Good CLIA: < 1% > 15% and % Moderate / Acceptable CLSI: < % > % Unacceptable < mg/dl: TE <15 mg/dl

20 GLUCOSE METERS / PERFORMANCES - Precision - Bias GRAPHICAL PRESENTATIONS

21 35 3 Y=X Accu_Chek_Aviva CV(%) 5% Roche Radiometer Accutrend_Sensor ABL_

22 Accu_Chek_Inform plasma_ Accu_Chek_Inform whole_blood_ Accu_Chek_Sensor plasma_ Roche Accu_Chek_Sensor whole_blood_

23 Ascensia_Contour plasma_ Ascensia_Contour whole_blood_ Bayer Elite Elite_XL

24 Glucocard Glucocard_Memory_ Glucocard_Memory Menarini Glucocard_Memory_PC

25 One_Touch_Ultra_One_Touch_Ultra_ Gluco_Touch Lifescan Precision_PCX

26 Precision_Xceed CV % , Precision_Xtra Abbott Freestyle ,,,, CV 91 9

27 GLUCOSE METERS / PERFORMANCES MOST SYSTEMS SHOW A POSITIF BIAS AS COMPARED TO THE VALUE SOME SYSTEMS SHOW A NEGATIF BIAS AS COMPARED TO THE VALUE A FEW SYSTEMS SHOW ALMOST NO BIAS AS COMPARED TO THE VALUE FOR SOME SYSTEMS IMPRECISION IS TO HIGH (CV > 5%)

28 9 5 Rapidpoint 5 Rapidlab 85 Rapidlab 15 NUMBER Of RESULTS PER TYPE OF GLUCOSE METER in the BELGIAN HOSPITALS Precision Xtra Precision Xceed Precision PCX One Touch Ultra/One Touch Ultra One Touch Ultra Smart One Touch Profile One Touch II One Touch Basic Glucose 1/1+ (whole blood) Glucocard X meter Glucocard Memory PC Glucocard Memory Glucocard Memory Glucocard Gluco Touch GEM 3 Freestyle Lite Freestyle Freedom Freestyle Elite XL Elite Ascensia Contour (whole blood) Ascensia Contour (plasma) Aeroset Accutrend Sensor Accutrend Accu-Chek Sensor (whole blood) Accu-Chek Sensor (plasma) Accu-Chek Inform (whole blood) Accu-Chek Inform (plasma) Accu-Chek Aviva 13 9 Accu-Chek Inform II (plasma) ABL POCT I vs. 8 POCT IV >>

29 Accu_Chek_Inform whole_blood_ Accu_Chek_Inform plasma_ Accu_Chek_Sensor whole_blood_ Accu_Chek_Sensor plasma_

30 One_Touch_Ultra_One_Touch_Ultra_ Gluco_Touch Glucocard_Memory_PC

31 15 %CV IN FUNCTION OF GLUCOSE CONCENTRATION CV% RELATIVE (%) IMPRECISION BEHAVES RECIPROCAL TO THE GLUCOSE CONCENTRATION 9 8 GLUCOSE (mg/dl) BIAS (%) VERSUS GLUCOSE CONCENTRATION BIAS IS SLIGHTLY POSITIVE IN THE NORMOGLYCEMIC RANGE Bias (%) Glucose (mg/dl)

32 CV EQA Median =,1% (3,8,) Mean =,5% Min:, Max:,9 7% of labs CV<= 5% Distribution of CV s per institute/ glucose meter surveys +/- institutes CV EQA 8 Median = 3,8% (3,,) Mean =,1% Min:,3 Max:,5 7% of labs CV<= 5%

33 5 8 POCT I (1 mg/dl) 35 8 POCT II (9 mg/dl) Frequency 3 1 Frequency CV (%) CV (%) 8 POCT III (58 mg/dl) 3 8 POCT IV (17 mg/dl) 5 5 Frequency 3 Frequency CV (%) CV (%)

34 7 5 CV(%) (median/ Institute) IN FUNCTION OF GLUCOSE CONCENTRATION CV(%) 3 1 P 75 <% Glucose (mg/dl) BIAS (%) VERSUS GLUCOSE CONCENTRATION 15 1 Bias (%) Glucose (mg/dl)

35 CONCLUSION I IMPRECISION OF CERTAIN LABORATORIES TO HIGH. OVER-ALL BIAS IS ACCEPTABLE, HOWEVER SOME GLUCOSE METERS SHOW SIGNIFICANT DEVIATIONS FROM THE REFERENCE VALUE AT LOW (clinically important) CONCENTRATIONS.

36 WHAT IS THE TRUE GLUCOSE CONCENTRATION IN THE SAMPLE??

37 DESING OF THE EQA SCHEME Testing model Samples Participants GLUCOSE METERS / PERFORMANCES Precision Bias Over-All performances PROBLEMS concerning EQA Program CONCLUSIONS

38 PROBLEMS with EQA PROBLEMS WITH SETTING? WHICH STANDARD - REFERENCE PREPARATION SHOULD BE USED? Should the NIST standard be used to adjust the values obtained by the hexokinase method? Should the GAS-ISE standard be used to adjust the values obtained by the hexokinase method? What about sample commutability?

39 Sample 9- from 1--9 to 3--9 Uncorrected results Laboratory Tue Wed Thu Fri Avg SD CV % Isala REF 1 VUmc REF Avg SD 3 CV % Sample 9- from 1--9 to 3--9 Corrected for: NIST using NIST measured values Laboratory Tue Wed Thu Fri Avg SD CV % Isala REF VUmc REF X 93 9 X 95. X 9 98 X Avg SD 1 1 CV %

40 WHAT IS THE TRUE GLUCOSE CONCENTRATION IN THE SAMPLE - which reference preparation should we use? SHOULD WE COMPARE TO THE REFERENCE VALUE (hexokinase) SHOULD WE COMPARE TO THE TYPE OF METER

41 Survey /(n) (glucose mg/dl) Unacceptable Results with respect to own method bias >% >+% >-% TOTAL (%) N (%) N (%) - / (37) mg/dl 5 (.%) (.1%) (.1% ) - / (59) 9 mg/dl 33 (1.3%) 31 5 (.%) 8 (1.1%) -7 / (37) 31 mg/dl 17 (.7%) 87 (.1%) 13 (.5%) -11 / (39) 3 mg/dl 1 (.9%) 11 9 (.%) 1 (.5%)

42 report settings all results sample 8-1 reporting in mg/dl calibration plasma n 3398 median bias -.1 % sd bias.5 % WIV/ISP REPORT validation all hex. ref. 17. mg/dl minimal n 1 legend: excellent ( <= 5 % ) good ( > 5 % and <= 1 % ) fair ( > 1 % and <= % ) unacceptable ( > % ) Standard report Median bias = + 8,% sd bias = 13,3%

43 CONCLUSION I WHAT IS THE TRUE VALUE OF THE TEST SAMPLE Which reference preparation should be used for target setting? SHOULD WE COMPARE TO THE REFERENCE VALUE (hexokinase) SHOULD WE COMPARE TO THE TYPE OF METER BOTH EVALUATIONS CAN BE APPLIED The importance is that POCT results correlate with the results of the core lab.

44 CONCLUSION II The EQA scheme provides the following useful information to the participating laboratory: Between-meter variability (%CV) Comparison between own results and the results obtained by the cohort using the same type of meter (peer group) Comparison between own results and over-all

45 To do by laboratories Results obtained in this EQA scheme, also depend on correct information obtained from the participants (type of calibration meters - ) EQA programs are not only evaluation the performance of the glucose meters, but alos the performance of the operators (.) TRAINING AND CONTINUOUS EDUCATION OF ALL STAFF MEMBERS INVOLVED IN POCT TESTING, ARE MANDATORY

46 To do by EQA organizers Efforts have to be made concerning the preparation of whole blood reference material for POCTglucose measurement. A study will be conducted on sample stability and sample commutability.