Downloaded 11 times
Uploaded byVickshayo Sss
Validation of laboratory tests with important guidelines
Validation ensures test methods are accurate and reliable. It establishes performance specifications and acceptance criteria. Methods are validated for accuracy, precision, reportable range, sensitivity and specificity using reference standards and statistical analysis. Pre-validation addresses purpose, guidelines and materials. Post-validation involves monitoring proficiency testing and system performance to maintain validity over time. Validation is important for conforming to standards, understanding error, and providing confidence in test results.
More Related Content
Similar to Validation of laboratory tests with important guidelines
![Chlamydial infection dx [Autosaved].pptx](https://cdn.slidesharecdn.com/ss_thumbnails/chlamydialinfectiondxautosaved-240203132505-221ff181-thumbnail.jpg?width=640&height=640&fit=bounds)
Validation of laboratory tests with important guidelines
- 1. VALIDATION OF LABORATORYTEST DEPARTMENT OF MICROBIOLOGY AND IMMUNOLOGY Presenter: Daniel Mwandu Facilitator: Dr. Doreen Komori Date: 22th Feb, 2024 Venue: Microbiology Lab
- 2. Presentation Outline • Introduction •Important of methods validation • Pre- validation • Methods validation parameters • Post validation monitoring
- 3. INTRODUCTION • Validation isthe process of testing a measurement procedures to asses it performance if inline with acceptance criteria. • Laboratory method validation is a process by which a method is determined to meet the requirement for the intended use. • It ensure accuracy, precision and reliable results • It help to determine the magnitude of error. • It ensure good customers services
- 5. ISO 15189:2022 ,Clause 7.3.3 The laboratory shall validate the following • Non standard methods • Laboratory designed/ developed methods • Standard methods used outside their intended. • Validated methods subsequently modified
- 6. Reason for establishmentof new methods • Clinical need of new analyte • Improve diagnosis and treatment due to short TAT. • Improve accuracy and precision • Reduce cost
- 7. • Clause 6.4.3.state that “ the laboratory shall verify the equipment's/methods to conforms the specified acceptability criteria. • Clause 6.4.4. state that “each equipment/ test method should be used as specified by manufacturer, unless validated by laboratory. • Clause 7.3.2.verification • Clause 7.3.3 validation
- 8. 3/4/2024 8 Performance characteristics VALIDATION Performedfor inhouse/modified methods It normally it done by manufacturer to establish the acceptance criteria VERIFICATION Confirm the performance claims by manufacturer
- 9. But I’m usingan FDA approved kit 3/4/2024 9 FDA APPROVED Conduct verification only Perform validation if some of the parameters were not validated Non -APPROVED Conduct validation and verification
- 10. Tests to validate •Waived test(simple test approved by FDA) i.e. UPT – No need of validation • Non-waived test(complex test) validation is needed i.e. Stain techniques. • Unmodified FDA approved- no need of validation • Modified /non-FDA approved need validation
- 11. Important of methodsvalidation • It ensure accuracy and reliable results • Understanding of uncertainty in the methods. • Provide confidence in the method through measuring robustness and ruggedness
- 12. Pre- validation Issue toconsider prior validation. Methods purpose and scope Regulatory guidelines eg SOPs Method development Parameter acceptance criteria A calibrated equipment to be validated. Materials: eg reagents, reference standard
- 13. Methods validation parameters Measurement type Description 01Trueness Reference intervals 02 Accuracy measure the closeness of the test results to the true value 03 Precision Repeatability, measure degree of agreement 04 Linearity (Reportable range) Ability to produce results, that are directly proportional to the analyte concentration within a specified range 05 Uncertainty Measure Standard deviation. 06 Sensitivity Detection 07 Specificity Ensure selectivity, without interference
- 14. Methods validation parameters Measurement type Formula 01Trueness Reference interval 02 Accuracy (TP+TN )/ (TP+TN+FP +FN)x100% 03 Precision (TP )/ (TP + FP)x100% 04 Linearity Y= mX + C. 05 Uncertainty(MoU) CV=SD/x 06 Sensitivity TP/(TP+FN) X100% 07 Specificity TN/(TN+FP) X100%
- 15. Trueness, Accuracy, andprecision
- 16. Precision • To performprecision test is running 20 of one sample depending on your schedule, • Analysis and interpret statics measure including mean, SD,CV, 2SD range and SD goal • The precision test will pass if the calculated SD is below the SD goal
- 17. Accuracy • It need40 different samples • Sample are tested in comparison of new method with existing accuracy method(gold standard) Measure the statics(Linearity) includes Correlation coefficient(R) greater 0.9 Slope for 95% CI is 1.000 Intercept for 95% CI is 0.000
- 18. Reportable range/linearity • Assessthe lowest and highest reliable results, • Used especially when there is two calibrators • Run 5 sample with known concertation in triplicate • Assess Linearity statics, then point out error rate, and evaluate if allowable • Error allowable is are proximity to reportable range
- 19. Sensitivity and Specificity •Done by comparing new method with gold standard method. • It involved running greater 100 sample in each methods. • Obtained results should be tabulated in two way table • Then, sensitivity and specificity will be calculated
- 20. Examples • A validationof a new rapid syphilis test kit, YYY was conducted at your laboratory. 500 specimen known to positive were tested and 479 results came out positive and others negative. A total of 506 known negative sample were tested and a total of 490 results were negative and others were positive. • The acceptability criteria for both Diagnostic sensitivity and diagnostic specificity is set at 98%. • Use a contingency table to calculate the validation results. • What would be your decision after obtaining the validation results?
- 21. GOLD STD TEST NEWTEST POSITIVE NEGATIVE TOTAL POSITIVE 479 16 495 NEGATIVE 21 490 511 TOTAL 500 506 1006
- 22.
- 23. MoU • It asystematically assess the factors influencing the measurement • It measure the actually parameter that should be included with any measurement results obtained • It measure existing doubt(degree from margin) • It tell us about the quality of testing methods • Errors are not the same as uncertainty
- 24. Post validation monitoring •To provide validation report which should includes performance specifications, results obtained, and final statement(performance was achieved or not) • Proficiency Testing eg EQA • System Performance Monitoring eg monitoring of deviation like LJ charts.
- 25.
- 26. References • ISO 15189:2022 •Analytical performance in accordance with CLSI guidelines, Update of 2017. • ICH Q2(R2) Validation Of Analytical Procedures Scientific Guideline, December 2023. • Published Articles.