Quality Assurance

Gift Ajay SamSr. Demonstrator/ Dy. Quality Manager

Department of Transfusion Medicine andImmunohaematology

CMC, Vellore

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Overview

• Introduction to quality– Definition of Quality– Definition of Quality Management– Core value of QM

• Quality assurance vs Quality control– Quality control– Proficiency testing– Calibration

• Documentation

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Quality?

• Conformance to requirements_ Philip Crosby.• Exceeding what customers expect form

service_ Paraguan and Berry.• User based, product based, manufacturing

based, value based and transcendent view_Gravin.

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Quality

“Quality is the degree to which a setof inherent characteristics fulfils

requirement”_ ISO 9000

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Quality Management

• Quality: Fulfilling requirements.• Management:– Plan– Organize– Staff– Lead/ direct– Control

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Quality + Management

Plan, organize, staff, lead and controlto fulfilling the requirements of thecustomer (patient/ lab service user).

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Core values of Quality Management

• Customer (lab service users) focus• Initiation from top management• Involvement of all staff• Process approach (profit maximization by waste

minimization)• System approach to management (Management

of interrelated processes)• Kaizen (Continual improvement)• Factual approach for decision making• Mutually beneficial supplier relationship

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Quality assurance vs Quality control

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3 major differencesQuality Assurance Quality Control

1 Management system toguarantee integrity of data.

Measurement used to checkquality of analytical data.

2 Everybody’s businessRestricted to a specific areaand performed by authorizedstaff.

3 Goal is value addition Goal is error prevention

4 Management strategy Error detection methodology9

QUALITY CONTROL

SelectionFrequencyEvaluation

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Quality Control- Selection

• Cover the analytical measurement range e.g.low, normal and high.• Product stability over a long period of time

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Frequency of QC runs• Stability of method (QC at least once in 24 hr or

more if manufacturer or lab determines so. (CLSIregulation, section 493.1256)• Risk of harm to patient– Clinical action that can be taken before error could be

detected.– Frequent QC can identify methodological problems

earlier.• Number of results to be repeated in case of

failure.

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QC at Immunohaematology

• In should cover a range of analyticalparameters i.e. grouping, rH typing, DAT, IAT.• In case of HGB quantification it should check

performance at low, normal and high.• In case of screening for TTI the controls should

be positive/ negative.• Other parameters to consider are cost and

availability.

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Evaluating QC results

• Control charts– Extreme- 1 value exceed 3SD– Bias- > 9 values on one side of chart.– Trend- > 6 continually points increase or decrease– Oscillation- Opposite directions over and over again.– On edge- 2 or 3 points exceed 2SD in same direction– Tendency- 9 (of 10) points on one side of the mean– Blissful ignorance- > 8 points in a row within 1SD,

distributed on both sides of the mean.

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Other features of QC runs

• QC run variability is usually expressed in termsof SD.• N= 20 as per CLSI 2006 guidelines.• It is recommended that the SD should be

established from a single lot of QC reagentsconsidering the values over a period of 6 – 12months. This will represent the variabilitybetter.

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Patient samples in QC

• Consistency of results with reagent lot changeand post calibration.• Delta check with previous results• Verification of consistency of results b/w

instruments.• Checking method performance as part of

instrument validation

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Proficiency testing/ EQA

• Evaluating method performance bycomparison of results with other laboratorieson the same set of samples.• Goal of PT/ EQA– Result harmonization among peers–Method accuracy (Need for calibration or any

other form of correction to ensure accurateresults).

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Calibration

• Performed using a calibrator.• Calibrator results are traceable to the highest

order of reference system.• Calibrators for instruments are usually

provided by the manufacturer themselves.• CLIA regulation 493.1255 recommends

methods have to be calibrated at least every 6months or more frequently if recommendedby the manufacturer.

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Calibration verification

• When no change in method performance hasoccurred it is acceptable to verify thatcalibration has not changed.• Verification is commonly done by using

calibrator as a “unknown material”.• The laboratory should establish the calibrator

target value for calibration verification, like+1 SD from target value can be considered.

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DOCUMENTATION

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Documentation

Indicators for good documentation:• Approved, reviewed and updated regularly.• Concise, legible, accurate and traceable.• Amendments & revision are identifiable.• Current version is available at points of use.• Follows change control procedure.• Obsolete documents separated, identified and

retained for defined amount of time.

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Documents of the QMSQualityManual

QSP/ SOP

Forms, checklist,Records.

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Document classification in QMS

Internal documents External documents Records

Documents

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Document classification in QMS

• Internal documents:– Documents/ reference material created by the

laboratory for use within the laboratory.– It is subject to the change control procedures

created by the laboratory.– It is approved by appropriate personal before

release for use by the laboratory personnel.– E.g. SOP, QM, QSP.

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Document classification in QMS

• External documents:–Maintained by the laboratory for reference

purposes.– Created by a third party and is formally published

for use.– Not subject to the change control procedure of

the laboratory.– E.g. ISO 15189; 2012 standard, published book.

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Document classification in QMS

Records• Proof/ evidence of activity.• They have a defined retention period.

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References

• Henrys clinical diagnosis and management bylaboratory methods, 22 edition.• The six sigma handbook revised and

expanded, Thomas Pyzedek.

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