310 likes | 465 Views
Quality Assurance Programmes for Laboratory Testing - An Overview . Elizabeth M. Dax National Serology Reference Laboratory, Australia www.nrl.gov.au. Quality Assurance.
E N D
Quality Assurance Programmes for Laboratory Testing -An Overview Elizabeth M. Dax National Serology Reference Laboratory, Australia www.nrl.gov.au
Quality Assurance Is the series of procedures that ensure that a correct result is achieved in a standard, reproducible and traceable manner.
Strategy development Trouble shooting Tertiary Reference Testing Quality Assurance System Kit Evaluation Performance Monitoring Specificity monitoringQuality ControlQAP(Batch testing) QUALITY PERFORMANCE QUALITY PERFORMANCE Pre-marketing
Equipment maintenance Specimen Collection QAP Safety Specimen Processing Training Testing QC Trouble Shooting Document Control/SOPs Reporting Other Management Controls
Quality Assurance Programme when Pre-market Post-market who, where NRL Laboratories Collaborative 6. Trouble shooting 3. QAP 1. Test Kit Evaluation what,how 4. QC 7. Re-evaluation 2. Batch Testing 8. Strategy development 5. Monitoring
Reasons Requirements Resources required Assess test, baseline data for QA Evaluation panels Regulations, serum panels, storage facilities 1.Evaluation (Re-evaluation)
Evaluations An evaluation is the appropriate assessment of the working performance of a test kit or an assay at a point in time.
1. Gather information on the kit 2. Examine the data EvaluationProcess 3. Write evaluation protocol 4. Select an evaluation panel 5. Perform the testing 6. Collate and analyse the data 7. Use the results
cutoff Frequency OD/Co Distributions of +ve & -ve samples in a “perfect” assay
Distributions of +ve & -ve Samples in a Serological Assay cutoff Frequency OD/Co
Distributions of +ve & -ve Samples in a Serological Assay • OTHER FACTORS • (unrelated to antibody) • High IgM • Rheumatoid factor • Sample related factors • Physical disruption cutoff Frequency OD/Co
Pathogenesis Seroconversion ARC/AIDS Asymptomatic Neutralising Antibody NAA viral load p24 Ag - Viraemia 4-5 weeks Up to 12 years 2-3 years
2. Pre-marketing Batch Testing • Usually by regulation • Usually by central laboratory • Other measures may be used “in-house”
Reasons Requirements Resources required Assess laboratory processes QAP panels, data processing,questionnaires Materials, QA coordination 3. Quality Assessment Programme
Quality Assessment(also known as proficiency testing) Method by which the quality of results generated by a particular laboratory is determined.
Quality Assessment Programme • Definition: • Method by which the entire testing process including the quality of results generated by a particular laboratory is assessed.
1A. Questionnaire 1B. New Participants 2. Preparation of Panels 3. Panel Distribution 4. Data Collection 5. Preliminary report 6. Data Analysis 7. Final report QAP Process
Reasons Requirements Resources required Check performance in use, check batches QC, data collection , batch testing Communication, infrastructure (Lab network) Quality Assurance ProgrammeElement: Performance Monitoring
4. Quality Control Programme Measures that are used to ensure that a test is working to the highest standard.
1. QC Sample 2. Determine Acceptable Ranges Process for the use of Quality Controls 3. Include in all test runs 4. Data Collection 5. Data Analysis 6. Accept or Reject Run 7. If Variation Identified Investigate
5 4 3 2 1 0 NRL QC Data Batch 2 Batch 3 Batch 1 Mean +2SD Mean Mean -2SD Invalid QC sample 15/8/97 10/3/98 date Invalid Kit Controls
Reasons Requirements Resources required Check performance in use, check batches QC, data collection , batch testing Communication, infrastructure (Lab network) 5. Performance Monitoring
Monitoring Assay Performance--ongoing evaluation of assay performance • Monitoring specificity • Monitoring sensitivity
Reasons Requirements Resources required Prevention of problems Panels, testing Quality control program, regulations 6. Trouble shooting
“Trouble- Shooting” Sorting out testing problems
Personnel Assay Reported problems Sample Equipment Methods Trouble Shooting
Reasons Requirements Resources required Assure testing is accurate & efficient Testing samples, collecting data Data collection and analysis skills 8. Strategy development
Strategy Development A strategy is a series of scientifically verified testing steps using a combination of assays that are employed to reach the correct diagnosis.
Strategy Development • Understanding the predictive values of the tests • Obtaining the appropriate data • Multivariant analyses of the data to assess the predictive value of test combinations used in sequence
Strategy development Trouble shooting Tertiary Reference Testing Quality Assurance System Kit Evaluation Performance Monitoring Specificity monitoringQuality ControlQAP(Batch testing) QUALITY PERFORMANCE Pre-marketing