QUALITY PATIENT CARE THROUGH PROFICIENCY TESTING

Not Just Talking Quality, But Investing in Quality

Naval Medical Center San DiegoLaboratory DepartmentQuality Assurance Unit

What I really need to know besides my “A,B,Cs”?

QA QC POCT PT

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

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

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

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

ENROLLMENT

Required for all analytes listed in the PT Enrollment Guide- Updated annually- Available at CAP website

www.cap.org-Included with order renewal forms

Why perform Linearity and Calibration Verification???

Requirements: CAP Laboratory Accreditation Program Checklist Question CHM.13400 (one of several relating to Calibration Verification) and Current CLIA Regulations Section 493.1255 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.

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 = 10-600 mg/dL

The AMR is based on the expectation that the signal is linearly related to glucose concentration over the 10-600 mg/dL range.

Verification of the AMR expectation is required because the calibrators do not define the complete measurement range.

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?

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

Reviewing your LN Evaluation Report

Example of LN2 Report (Calcium)

Example of LN2 Report (Calcium)

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?

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

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

REPORTED CAUSES OF PT FAILURES

CLERICAL ERRORS

Post Analytic Phase Same importance as testing errors Examples:

Transcription Method/Reagent/Instrument codes Missing Information (TNP, </>, etc)

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

Methodologic Issues

Mechanical difficulties Instrument Software Problems Frequency of CALIBRATION Inadequate Reagent Performance Inadequate Maintenance Other instrument malfunctions

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 theappropriate use of these exception codes should this berequested during a laboratory inspection.

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

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

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

PT Monitoring by Accreditation Program

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

Example of Unsuccessful Proficiency Testing Performance:

IgA FAILED on two out of 3 events.

What will be your course of action:

1. Continue testing and provide CAP with credible program of corrective action

2. Voluntarily cease patient testing and investigate the failure

3. Conduct thorough investigation

IgA Unity Laboratory Comparison Report

<2.0

SDI/CVR

IgA Levy Jennings

POOR CALIBRATION

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 performedPrecisionLinearityCorrelation Studies

CONCLUSION:

Proficiency Testing monitors laboratories' continuing performance in a way that:

–Improves patient care –Protects the public’s health

References:

www.cap.org