John Gatimu University of Nairobi/University of Washington Research Laboratory What Is Not Mentioned In User Manuals: A Case Study of Quality Control in a Flow Cytometry Laboratory

Quality Assurance in the Flow Cytometry Lab Systematic activities to provide confidence in results: SOPs, records, documentation Proficiency testing (EQA) and internal quality Assurance (IQA) Staff training and competency Instrument maintenance and monitoring Improvement through corrective action However, this is not always enough…

The Need to Validate Quality Parameters Not all industry-derived guidelines are applicable to all labs Determine which parameters to validate: instrument performance reports ranges for controls Determine how to validate parameters Comparison analysis (intra and inter analysis)

Objectives For this case study, we focused on 3 quality areas: 1. Improving Levy-Jennings plots for IQA data 2. Analyzing EQA samples from two sources 3. Assessing specific instrument performance parameters

Internal Quality Assurance (IQA) Questions to ask when choosing an IQA sample Does it work with my instrumentation and measure the correct analytes? What is the stability of the sample? How will performance be measured? What is the plan if IQA does not pass?

L-J Plots for IQA At the beginning of a lot, all values appear within 2SD

L-J Plots for IQA: the problem As more data is added, SD shifts and some points fall outside of the 2SD range

L-J Plots for IQA: the Solution At the beginning of a new reagent lot use: Historical CV = SD/ mean

IQA: how the problem was solved Example: Company range: Laboratory Range: Company range

Corrective action for out of range values Confirm IQA sample, Machine - repeat if necessary Still out of range: rerun the same aliquot set up a new aliquot stain samples until next day consult the BD service engineers

External Quality Assurance Choose a program that fits your needs: Important Questions: Can the sample be treated as patient samples? Is the frequency of EQA acceptable? How much time does it take to get feedback- results? What is the plan for not passing EQA?

Evaluating Different EQA Programs Analysis of EQA samples from 2 EQA companies Company A: failure rate up to 70% and 90% for CD3 and CD8 respectively when using automated gating Company B: Identified as consistent with normal lab practice

Monitoring Instrument Parameters Areas monitored: Calibration parameters The Lasers Daily calibration to monitor all Instrument parameters: Optical alignment Compensations PMT voltages Lasers

Incorporation of QA validation into Correction Action Plan Algorithm for out-of-range values is specific for different parameters (compensation, IQA etc) 1 st day out of rangePerform a short clean and monitor system 2 nd day out of range Prime fluidics, tighten sheath, use new reagents, short/long clean 3 rd day out of rangeConsult with BD NOTE: Results will not be released if all parameters do not pass If compensation falls out of range according to the BD LJ QC report:

Monitoring the lasers

Conclusions Industry-provided guidelines can be too broad for the purposes of the flow laboratory Importance of customizing the reporting of IQA results using L-J plots Lab found an EQA scheme consistent with normal practice Recommendation: Labs should thoroughly assess guidelines to assure they meet needs of the lab

References and Acknowledgements ance/1205.pdf ance/1205.pdf /default.stm (FDA ASR policy) Barbara Lohman-Payne Judd Walson Tanja Hart Amy Liu Michele Merkel Nick Bright Anna Wambugu