Alan NealCharge ScientistPathlab Waikato

My Opinion & approach

Quality Assurance in the21st Century

…. in 2019?• few laboratories today actually use quality goals

when managing the quality of their testing processes

• Laboratories continue with statistical QC procedures that are selected without consideration of the quality needed for the test and sometimes without consideration of the performance observed for the method……..

•Way forward – Risk management

www.westgard.com

ISO 15189 - 2012

Specific criteria - no further clarification

Title

https://www.elitecme.com/resource-center/laboratory/calibration-verification-webinar/

Calibration:

Assumed that all haematology analysers have a linear response over measurable range, this characteristic enables the use of single point calibration.

Calibration performed:

• Analyser set up• As directed by manufacture• Failure of calibration verification

In a previously stable analyser, Calibration is the last option in the resolution of poor performance, all other options must be excluded prior to this

procedure.

Calibration Verification:

Calibration verification frequency 6 monthly*, also:

• Direction of manufacture(s)• Direction of laboratory QMS• Review of reagent Lot to Lot variance• Major maintenance• Replacement of critical parts• Complete reagent change• QC trouble shooting

*Calibration Verification – Automated cell counters:

If:

• follow manufactures instructions for operation• two level of controls material tested each day• Control materials within acceptable limits

Then this fulfils the calibration verification criteria

Also• Three or more levels of calibration material &• Includes Low, Mid & High values &• Performed at least six monthly

Then this would fulfil the calibration verification requirements

Calibration material* – contains a ‘known’ amount of analyte*Proficiency or control materials with know values are examples of calibration material

*Calibration Verification – Automated cell counters:

Therefore if using IQC & / or EQA scheme and this has:

• Three or more levels of calibration material &• Includes Low, Mid & High values &• Information over 6 month period &• Good performance

Then this would fulfil the calibration verification requirements

Accuracy & Precision via IQC review:

• Only perform reproducibility check if high CVI• Risk of this approach – Group think / Bias!

Different approach but same outcome:

Pathlab Approach – Calibration / Precision:

Primary Analyser Secondary Analyser(s)- ‘Truth’ - Clone of Primary (xM xB values)- Calibration verification annual* - IQC’s compared to primary analyser- All EQA’s analysed - Monthly Cal validation (Intra-analyser comparison)

- (Review Web based IQC) - (Review Web based IQC)

Identical set up to primary analyser – xB, xM (targets and limits).

*Unless concern Re analyser performance – EQA, IQC poor performance? Of any value

Consideration(s):– Calibration / Calibration verification processes:

Matrix effect

Calibration material artificial (Alligator, fixed etc. & doesn’t behave the same as native

blood.

Summary….• Customise QA procedures for

individual assays based on their quality requirement, performance & risk

• Less (effort) for more (reward)

• Minimise false rejections in order to maximise response to real problems

• Spend time & effort on tasks that need it & not on those that don’t !!