Quality Assurance Programmes for Laboratory Testing An Overview[1]

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. Quality Assurance System Kit Evaluation Performance Monitoring Specificity monitoring Quality Control QAP (Batch testing) Strategy development Trouble shooting Tertiary Reference Testing QUALITY PERFORMANCE QUALITY PERFORMANCE Pre-marketing Specimen Collection Equipment maintenance QAP Specimen Processing Safety Training QC Testing Trouble Shooting Document Control/SOPs Reporting Other Management Controls Quality Assurance Programme Pre-market NRL 1. Test Kit Evaluation 2. Batch Testing Post-market Laboratories 3. QAP Collaborative 6. Trouble shooting 4. QC 5. Monitoring 7. Re-evaluation 8. Strategy development 1. Evaluation (Re-evaluation) Reasons Assess test, baseline data for QA panels Requirements Resources Evaluation Regulations, required serum panels, storage facilities 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 3. Write evaluation protocol 4. Select an evaluation panel 5. Perform the testing 6. Collate and analyse the data 7. Use the results Distributions of +ve & -ve samples in a “perfect” assay Frequency cutoff OD/Co Distributions of +ve & -ve Samples in a Serological Assay Frequency cutoff OD/Co Distributions of +ve & -ve Samples in a Serological Assay Frequency cutoff OTHER FACTORS (unrelated to antibody) •High IgM •Rheumatoid factor •Sample related factors •Physical disruption 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 “inhouse”  3. Quality Assessment Programme  Reasons Requirements laboratory processes QAP Assess  panels, data processing,questionnaires Materials,  Resources required QA coordination 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 Quality Assurance Programme Element: Performance Monitoring Reasons  Check performance in use, check batches data collection , batch testing infrastructure (Lab network) Requirements  QC, Resources  Communication, required 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 3. Include in all test runs 4. Data Collection 5. Data Analysis 6. Accept or Reject Run 7. If Variation Identified  Investigate NRL QC Data 5 Mean +2SD 4 3 2 1 0 15/8/97 Mean Mean 2SD Invalid QC sample 10/3/98 date Invalid Kit Controls 5. Performance Monitoring Reasons  Check performance in use, check batches data collection , batch testing infrastructure (Lab network) Requirements  QC, Resources  Communication, required Monitoring Assay Performance-ongoing evaluation of assay performance Monitoring specificity  Monitoring sensitivity  6. Trouble shooting  Reasons  Prevention of problems Requirements  Resources required   Panels, testing  Quality control program, regulations “Trouble- Shooting” Sorting out testing problems Trouble Shooting 8. Strategy development  Reasons Requirements  Assure testing is accurate & efficient samples, collecting data collection and analysis skills   Testing  Resources required  Data 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  Quality Assurance System Kit Evaluation Performance Monitoring Specificity monitoring Quality Control QAP (Batch testing) Strategy development Trouble shooting Tertiary Reference Testing QUALITY PERFORMANCE Pre-marketing