EQA EQAS Results interpretation (1).pptx

Islamabad Diagnostic Centre F-8 Islamabad External Quality Assessment and Results Evaluation What is EQA  An external quality monitoring scheme  Consistsof “blinded” samples that closely simulate clinical material A technique to challenge a labora...

Islamabad Diagnostic Centre F-8 Islamabad External Quality Assessment and Results Evaluation What is EQA  An external quality monitoring scheme  Consistsof “blinded” samples that closely simulate clinical material A technique to challenge a laboratory’s internal QC methods and procedures. A program to assess laboratory performance and the ability to determine the “correct” result.  Also termed Proficiency Testing (PT) EQA  important for improvement  a measure of laboratory performance Principle of EQA Schemes What is the purpose of EQA  Challenge participants quality systems  Encourage inter-laboratory comparability  Encourages improvement  Provides insight into national /international levels of performance  Allows poor performance to be addressed  Excellent source of reference material  Required in licensing (accreditation) Quality Improvement  Provides early warning for systematic problems associated with kits or operations;  Provides objective evidence of testing quality  Indicates areas that need improvement  Identifies training needs  EQA helps to ensure physicians, patients and health authorities, that the laboratory can produce reliable results. What is a good EQA scheme  Internationally recognised  Has many participating laboratories  Numerous and varied samples  Several distributions throughout the year  Rapid report turnaround  Preferably electronic result entry and report return  Friendly and helpful – advice in trouble-shooting  Educational EQA Process Management Process chose the right Scheme for your needs analyze EQA samples in good time treat EQA samples same as patient monitor and maintain records investigate deficiencies manage corrective action efforts communicate outcomes EQA Should Lead to Actions  The Benefits of EQA The Laboratory A valuable tool for:  System confidence  Self assessment & recognition  Public confidence The Patient  Knows the system is working together to ensure the public receives accurate and useful information EQA Sample Processing QA Person will receive the samples and hand over the samples along with the processing form to the concerned department.  External quality control samples will be run by concerned section staff after verifying internal quality controls. After analyzing the data will be submitted to QA Coordinator who will enter the data in respective accounts provided by the EQA body. Left over sample of external QC sample will be kept till the final report of the sample received. EQA Sample Processing  Once labeled and booked Specimen Reception pass specimens (with paperwork) to Automated laboratory  Important to analyze EQA samples on day of receipt – if not possible should be stored appropriately and delay in analysis recorded on paperwork  Any preparation instructions provided should be adhered to ‘exactly.’ Especially important when reconstituting lyophilized samples e.g. Receiving Reports from EQA Bodies  After compiling data EQA bodies provide reports available online which can be printed and kept in files and emailed to the concerned Persons / Departments.  QA Coordinator will print report of each cycle and analyze results. If all results pass the evaluation; report will be placed in department EQA file after discussing with AGM LAB.  However, if any parameter does not pass the evaluation and deviates from accepted range, QA Coordinator will initiate CPA.  QA Coordinator will call the CPA meeting and discuss the results with concerned section supervisor/ Manager, AGM lAB who will find root cause AND will take corrective action. EQA performance problems  Pre-examination: The sample may have been compromised during preparation, shipping, or after receipt in the laboratory by improper storage or handling. The sample may have been processed or labeled improperly in the laboratory  Examination: The EQA challenge materials may exhibit a matrix effect in the examination system used by the participating laboratory. Possible sources of analytical problems include reagents, instruments, test methods, calibrations and calculations. Analytical problems should be investigated to determine whether error is random or systemic. Competency of staff will need to be considered and evaluated  Post-examination: The report format can be confusing. Interpretation of results can be incorrect. Clerical or transcription errors can be sources of error Interpretation of EQA Results Interpretation of EQA Results Interpretation of EQA Results Peer Group in EQA  In a peer-reporting program, a group of laboratories use the same brand and model of instruments to analyze the same specimens— usually specially calibrated QC materials with the same lot numbers—and submit their results to a central facility. The system provider then characterizes the performance of this group of laboratories—the peer group—by calculating the means and standard deviations (SDs) of the group and its individual members, and examining the results to identify outliers. Benefits in Peer Grouping  A very good estimate of the bias, repeatability, and reproducibility of a laboratory’s analytical processes compared to those of a peer group of laboratories.  An easy method of detecting error trends, so that corrective actions can be performed in a timely manner.  From the behavior of a process analyzed via a peer-reporting program, it may be possible to deduce how the process will behave during a future proficiency testing examination— presuming that the matrices of the QC materials and the proficiency testing samples are similar.  Potential for reducing the proficiency testing of duplicate instruments performing the same processes, since the peer- reporting program is being used to monitor the long-term stability of all of the instruments.  Effective documentation of a laboratory’s performance for specific processes, throughout the entire period of participation. z-score  The z-score is the number of standard deviations a control result is from the expected mean.  Use the following formula to calculate the z-score: Z-score = reported value – assigned value standard deviation  A z-score of 2.3 indicates the observed value is 2.3SD away from the expected mean. A data point with this z-score violates the 12s rule, but not the 13s rule. Standard deviation  The standard deviation measures a test's precision; that is, how close individual measurements are to each other. (The standard deviation does not measure bias, which requires the comparison of your results to a target value such as your peer group.) The standard deviation provides an estimate of how repeatable a test is at specific concentrations. Test repeatability can be consistent (low standard deviation, low imprecision) or inconsistent (high standard deviation, high imprecision).  It is optimum to have repeated measurements of the same specimen in order to have results as close to each other as possible. Good precision is especially important for tests repeated regularly on the same patient in order to track treatment or disease progress. Mean, CV, Bias Mean: The mean for a group of data points is simply the calculated average. The mean provides a laboratory's best estimate of the analyte's "true" value for a specific level of control. The mean ± a predetermined number of standard deviations represents the error expected in a test when the analytical system is stable. Coefficient of Variation (CV): The coefficient of variation is the ratio of the standard deviation to the mean. Express CV as a percentage.  Bias: Bias measures how far your observed value is from a target value. Determine bias by a reference value or estimate Lab. Bias %= Lab Mean - Concensus Group mean *100 Concensus Group mean Mode  Evaluate laboratory performance: By comparing a laboratory's results to the mode, EQA providers can assess their performance and identify potential deviations or biases.  Set target values: The mode can serve as a target value for laboratories to strive for, ensuring that their results are consistent with peer group performance.  Monitor trends: Tracking changes in the mode over time helps EQA providers detect shifts in laboratory performance or instrument drift.  Improve quality: By analyzing the mode and associated data, EQA providers can identify areas for improvement and implement measures to enhance laboratory quality. The mode in EQA serves as a reference point for evaluating laboratory performance, setting targets, monitoring trends, and driving quality improvement. Why Analysis of EQAS reports is important ? Proper analysis of EQAS testing results can reveal : problems  even before failure in EQAS or even an adverse patient result Potential problems can be recognized by  recognizing patterns from graphs Review both the present cycle results as well as  performance from previous cycle for the same analyte Graphs of Z score or SD or RMZ or % deviation for  trends Otherwise trends will be missed  How to recognise problems ?  Results may consistently be different from the target peer group mean - All results on one side of the mean (may be close to mean or at variable distances from mean) Systematic Error  Majority of results are close to the target value but some show larger deviation s on one side or both side of mean – Random Error  Reasons and hence corrective action differs