1. THROUGH PROFICIENCY TESTING
QUALITY PATIENT CARE
THROUGH PROFICIENCY TESTING
Not Just Talking Quality, But Investing in Quality Naval Medical Center San Diego Laboratory Department Quality Assurance Unit

2. What I really need to know besides my “A,B,Cs”?QA QC
POCT PT

3. OBJECTIVES
Discuss regulatory aspects and impact of proficiency testing (PT)
Approaches to effectively manage and fully utilize PT
List investigative techniques used to determine causes of poor PT performance and describe effective corrective actions
Understand how “Linearity” relate to the accreditation process
Explain techniques to perform the appropriate verifications of AMR and CRR
Common Analytical Exception codes

4. CAP Proficiency Testing
Allows laboratories to evaluate their performance and improve the accuracy of the patient results
Results evaluated using comparable peer groups from comprehensive database of laboratories

5. PROFICIENCY TESTING DO’s
Samples are tested on all shifts by technicians who routinely test patient samples
All surveys performed are treated as real patient samples. This includes using the same test methods for quality control, patient testing, workload accounting, verification and reporting of results.
NOTE: This only applies to analytes that are tested in-house.
Personnel who routinely analyze patient samples will integrate all PT within the routine workload

6. Proficiency Testing DON’Ts
Test samples differently than patient specimens
Have the same people always do testing
Refer samples to another laboratory
Discuss results before reporting
Use PT sample for other purposes before submission date deadline

7. ENROLLMENT Required for all analytes listed in the PT Enrollment Guide
- Updated annually
- Available at CAP website
-Included with order renewal forms

8. Why perform Linearity and Calibration Verification???
Requirements: CAP Laboratory Accreditation Program Checklist Question CHM (one of several relating to Calibration Verification) and Current CLIA Regulations Section for most analytes.
Linearity evaluations give information about what’s occurring “near the extremes," the high and low ends of the measurement range.
LN Surveys are particularly useful in calibration verification – identify imprecision problems before they become noticeable in other ways.
Calibration Verification provides proof that the measurement system calibration has not changed since the last calibration event.

9. Why does AMR need to be verified?
Example: typical serum glucose method
Low calibrator = reagent blank (0 mg/dL)
High calibrator = 356 mg/dL
AMR = mg/dL
The AMR is based on the expectation that the signal is linearly related to glucose concentration over the mg/dL range.
Verification of the AMR expectation is required because the calibrators do not define the complete measurement range.

10. Clinically Reportable Range
Extension of the AMR based on clinical requirements.
Established once when method is implemented
Does not need to be verified on a recurring schedule
Values outside the CRR are reported as < or > a numeric value.
Checklist question: Are dilution protocols and diluents (or concentration protocols) specified for all methods for which the CRR exceeds the AMR?

11. AMR: how close to low and high limits
To verify acceptable clinical performance
For low limit: use clinical judgment, e.g.
creatinine, 0.2 or 0.3 mg/dL
For high limit: within 10-15% of upper limit of AMR

12. Reviewing your LN Evaluation Report
Example of LN2 Report (Calcium)

13. Example of LN2 Report (Calcium)

14. Example of a Non-Linear Result
Loss of recovery at the high end of the AMR
-Check reagents, calibrators, QC
-Are the results clinically significant?

15. PARTICIPATION In addition to enrolling and testing samples, you must:
-Ensure results are sent either electronically or via fax
-Ensure they are sent by the deadline
-Ensure all faxed pages are received
NOTE: Non-participation (failure to receive results)= UNSATISFACTORY

16. SATISFACTORY PT PERFORMANCE
80% for regulated analytes and other analytes that have at least 5 challenges per PT event
Percentage varies for analytes with fewer than 5 challenges

17. REPORTED CAUSES OF PT FAILURES

18. CLERICAL ERRORS Post Analytic Phase Same importance as testing errors
Examples:
Transcription
Method/Reagent/Instrument codes
Missing Information (TNP, </>, etc)

19. TECHNICAL ISSUES Directly attributable to human actions:
Reconstitution
Specimen Mix-up
Improper Specimen Handling
Incorrect Instrument Handling
Failure to follow testing kit instructions
Morphologic Misinterpretations

20. Methodologic Issues Mechanical difficulties
Instrument Software Problems
Frequency of CALIBRATION
Inadequate Reagent Performance
Inadequate Maintenance
Other instrument malfunctions

21. Exception Codes ANALYTICAL PROBLEM
(Leave the result area blank and fill the bubble for the appropriate Exception Code).
11 Unable to analyze (documentation be provided by laboratory).
22 Result is outside method/ instrument reportable range.
33 Specimen determined to be unsatisfactory after contacting the CAP.
*It is the laboratory’s responsibility to document the
appropriate use of these exception codes should this be
requested during a laboratory inspection.

22. Additional Tips
Keep original worksheets and instrument print-outs with the PT file
Make sure every less than acceptable result is followed up and documented
Confirm that corrective actions make sense and actually fix the problem

23. UNSATISFACTORY PT PERFORMANCE
Laboratories that have unsatisfactory performance for 1 or more analytes on an event will receive PTES Exception Summary (PTES) report.
Investigate the problem
Determine cause
Implement Corrective Action
RESPONSE TO LAP is not required

24. UNSUCCESSFUL PT PERFORMANCE
Is unsatisfactory performance on 2 of 3 PT events
Laboratory will receive a PT Exception Summary (PTES) report
Laboratory must suspend testing or implement plan of corrective action
LAP must approve laboratory’s action

25. PT Monitoring by Accreditation Program

26. CORRECTIVE ACTIONS
Design a process to verify clerical entries prior to result submission
Retrain testing personnel as to the proper procedures for sample preparation, testing and reporting
Modify/Narrow QC acceptance range to detect problems sooner
Evaluate/increase frequency of calibration
Perform Instrument Function Verification (Precision, Linearity, Correlation)
Revise Procedure to reflect corrective actions

27. What will be your course of action:
Example of Unsuccessful Proficiency Testing Performance: IgA FAILED on two out of 3 events.
What will be your course of action:
Continue testing and provide CAP with credible program of corrective action
Voluntarily cease patient testing and investigate the failure
Conduct thorough investigation

28. IgA Unity Laboratory Comparison Report
<2.0
SDI/CVR

29. IgA Levy Jennings
POOR CALIBRATION

30. Identified Cause of Failure: Poor Calibration
Corrective Measures to prevent reoccurrence:
Daily review of calibration and QC
More frequent monitoring of LJ charts to catch trends and shifts that could indicate calibration curve issue
Method validation of IgA method was performed
Precision
Linearity
Correlation Studies

31. CONCLUSION:
Proficiency Testing monitors laboratories' continuing performance in a way that:
–Improves patient care
–Protects the public’s health

32. References: