Quality Management in Medical Laboratory

Internal Quality ControlDr. Adel A. ElazabAssociate Professor of Clinical PathologyFaculty of MedicineAin Shams University, Cairo, Egypt

Quality Concept

All management systems are focused on getting the job done.

Some have been effective in making larger profits while others have been effective in providing a better service.

More efficient and effective management guarantees the job to be done in the proper way.

Stages of QualityNCCLS Approved Guideline - GP26A

STAGE ACTIVITIES PERFORMED1. TOTAL QUALITY MANAGEMENT Management approach centered around

“Customer Satisfaction”2. QUALITY MANAGEMENT All of the below plus the economic

aspects of “Cost of Quality”3. QUALITY SYSTEM “Comprehensive and Coordinated”

efforts to meet quality objectives4. QUALITY ASSURANCE Systematic activities to provide

“Confidence” that the organizationmeets requirements for quality

5. QUALITY CONTROL Operational techniques applied to“Specific Tasks” for quality andregulatory compliance.

Stages of Quality

Quality : degree to which a set of inherent characteristics fulfills requirements

Quality control: part of quality management focused on fulfilling quality requirements

Quality assurance: part of quality management focused on providing confidence that quality requirements will be fulfilled

Quality management: coordinated activities to direct and control an organization with regard to quality

The March of Quality Management

1942-52 US Military develop requirements for contractors for shell, aircraft, missile suppliers (Quality without 100% inspection)

1947 International Organization for Standardization (ISO) created to adopt industrial standards

1959 US Department of Defense established MIL-Q-9858 quality management

1963 MIL-Q-9858 is internationalized as an ABCA standard

1968 NATO adopts MIL-Q-9858A as Allied Quality Assurance Publication 1 (AQAP-1)

1979 British Standards Institute (BSI) developed AQAP-1 for civilian use BS 5750

Quality Management System

A laboratory QMS is a systematic approach that describes, documents, implements, measures, and monitors the effectiveness of laboratory work operations in meeting international, national, regional, local, and organizational requirements and promotes the efficient use of resources.

Outcomes of QMS:-

Quality System Essentials The goal of an efficient and effective laboratory is

to provide consistently accurate results in a timely manner with the most judicious use of resources.

Quality system essential: an essential building block of a quality management system that addresses, at a minimum, regulatory and accreditation requirements within a specific topic needed to fulfill those requirements and stated quality objectives.

The 12 quality system essentials (QSEs) are universal and applicable to any size laboratory, whether simple or complex, in any laboratory discipline.

Calibration: the process of testing and adjustment of an instrument, kit, or test system to provide a known relationship between the measurement response and the value of the substance measured by the test procedure

Effectiveness: the extent to which planned activities are realized and planned results achieved

Efficiency: the relationship between the results achieved and the resources used

Non-QMS processes – processes that are not contained in either the QSEs or in the laboratory’s path of workflow, such as those within the finance, sales, or marketing functions.

Path of workflow: the sequential processes in a laboratory’s activities that transform a request for examination into the laboratory information that is captured in the report of results.

Plan: written account of intended future course of action aimed at achieving specific goal(s) or objective(s) within a specific timeframe and explains in detail what needs to be done, when, how, and by whom.

 OrganizationCustomer FocusFacilities and SafetyPersonnelPurchasing and InventoryEquipmentProcess Management

 Pre-examinationExaminationPost-examination

Documents and RecordsInformation ManagementNonconforming Event ManagementAssessmentsContinual Improvement

Pree-xaminationExaminationPost-examinationInformation

Management

Quality System Essentials - those elements which must be applied to all operations in the service’s path of workflow

Path of Workflow - as it relates to the processes involved in the pre-, during and post- phases of delivery of services with the laboratory as an example

Laboratory Path of Workflow

Quality SystemEssentials

OrganizationPersonnelEquipmentPurchasing/ InventoryProcess ControlDocuments/ RecordsOccurrence ManagementInternal AssessmentProcess ImprovementService and Satisfaction

Post Information Preanalytical Analytical Analytical Management

Quality system essentialsapply to all operations

in the path of workflow

Patient Test Specimen Specimen Specimen Testing Laboratory Results Post-test Laboratory Interpretation/Assessment Request Collection Transport Receipt Review InterpretationReport Specimen Information Consultation

Management Testing System

The Quality Toolbox

The Quality Toolbox

Lean

RISKFMEA

Six Sigma

Metrics

Surveys

Statistics

The Quality Toolbox

Mega-Tools◦ Lean◦ Six Sigma ◦ Priority Matrices and

Risk Assessment

Tools/Techniques◦ Balanced Scorecards◦ Brainstorming◦ Control Charting◦ Flow Charting◦ Quality Indicators◦ Surveys

Tools in the Toolbox

QUALITY ASSURANCEPROGRAMME

! Internal Quality Control (IQC) Procedures

! External Quality Assessment (EQA)

! Quality Management

Internal Quality Control (IQC)Procedures

⇒ Done during daily routine work⇒ Provides an immediate control⇒ Errors are corrected immediately⇒ Routinely collect and analyze data

from every test run or procedure

Why do we need Internal Quality Control?

! Ensure that test results are reliable! Ensure that test results are

reproducible! Control quality of daily routine work

Internal Quality Control

Monitoring quality of laboratory testing, accuracy and precision of laboratory

results

Precision and Accuracy Precise and Inaccurate Precise and Accurate

Precision and Accuracy Imprecise and Inaccurate Imprecise and ??

Accurate

Internal Quality Control It ensures continual check that the established

reliability of the laboratory’s work does not fluctuate and that reports are validated before they are released.

It is based on monitoring the procedures which are actually used for the tests in the laboratory. It includes:

· Control charts with tests on control materials· Duplicate tests on all specimens or on a proportion

of the specimens· Delta check, comparing current test results with

previous results· Consistency of mean values of patient data

Analytical run: is an interval within which the accuracy and precision of the measuring system is expected to be stable; between which events may occur causing the measurement process to be more susceptible (i.e., greater risk) to errors that are important to detect.

Each lab should define the run length because the operating conditions, workload, and application of the measurement procedure in the laboratory may differ from nominal conditions evaluated by the manufacturer.

Based on:◦ The expected stability of the measurement

procedure◦ The number of patient samples typically being

analyzed◦ Cost of reanalysis in the event of a QC failure,◦ Workflow patterns◦ Operator characteristics◦ The clinical impact of an undetected error condition

existing for a period of time before the next QC measurement(s)

◦ Stability of an analyte in patient samples

QC Quantitative Tests

Use 2-3 levels of controls covering the medical decision points

At least 20 control values over a period of 20-30 days for each level of control

Perform statistical analysis Develop Levey-Jenning chart Run -regularly- with patient samples Monitor control values on chart using

Westgard rules Take immediate corrective action, if

needed Record actions taken (if any)

QC Quantitative Tests QC material must be available in large

quantities stored in small aliquots (Ideally should last for at least 1 year)

Always consider as Biohazardous Requires very accurate reconstitution if

needed Always deal with and store as

recommended by manufacturer

Analysis of Control Materials

Need data set of at least 20 points obtained over 20-30 days better by different operators in different times of day

Calculate mean, standard deviation, Coefficient of variation and determine target ranges

Develop Levey-Jenning charts Plot –on the chart- control values each

run/ day Make decisions regarding acceptability

of run using Westgard rules Monitor over time and at defined

intervals

1. 192 mg/dL2. 194 mg/dL3. 196 mg/dL4. 196 mg/dL5. 160 mg/dL6. 196 mg/dL

7. 200 mg/dL8. 200 mg/dL9. 202 mg/dL10. 255 mg/dL11. 204 mg/dL12. 208 mg/dL13. 212 mg/dL

Calculation of the Mean: Outliers

Levey-Jennings Chart Calculate the Mean and Standard Deviation;Record the Mean and +/- 1,2 and 3 SD Control Limits

80

85

90

95

100

105

110

115

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Day

Mean

+1SD

+2SD

+3SD

-1SD

-2SD

-3SD

Levey-Jennings Chart -Record and Evaluate the Control Values

80

85

90

95

100

105

110

115

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Day

Mean

+1SD

+2SD

+3SD

-1SD

-2SD

-3SD

Findings Over Time

Ideally should have control values clustered around the mean (+/-2 SD) with little variation in the upward or downward direction

Imprecision = large amount of scatter around the mean. Usually caused by errors in technique

Inaccuracy = may see as a trend or a shift, usually caused by change in the testing process

Random error = no pattern. Usually poor technique, malfunctioning equipment

ERRORS

Random Error (RE): Imprecision

Causes:1. Pipetting error2. Temperature error3. Mixing defect4. Machine need

troubleshooting

Systematic Error (SE): Inaccuracy

Causes:1. Deterioration of

control material2. Deterioration of

calibrator3. Deterioration of

reagents

Westgard Rules Allows determination of whether an

analytical run/s (in control) or (out of control)

http://www.westgard.com/images/mrf14.gif

October 1, 2008

October 1, 2008

Westgard Multirules

When you're running 2 or 4 control levels, use the rules: 13s/22s/R4s/41s/10x

When you're running 3 control levels, use a set that works for multiples of threes:13s/2of32s/R4s/ 31s/12x

When a Rule is Violated

Rejection rule = Out of control=1. Stop testing2. Identify and correct problem3. Repeat testing on pt samples and

control4. Don’t report pt results until problem

is solved and controls indicate proper performance

When a Rule is Violated

Change one variable at a time to troubleshoot an out of control test.

The variables are usually common to all instruments or procedure systems and include the following:

1. Try a fresh vial of QC 2. Try a new reagent (same lot) 3. Try a new consumable (water, part, solution, tubing)

if applicable. 4. Try a new reagent (new lot) 5. Recalibrate (current calibrator) 6. Recalibrate (new lot calibrator) If a system cannot be brought into control,

notify senior staff. Do not process patient samples for the test affected.

Overlap New Lot of Controls

When changing to a new lot number of control material, ideally there should be an overlap period while the new material is being analyzed to establish the new control limits.

In cases where the overlap period is not sufficient, it is possible to establish the mean value for the new control material in a short time, over say a five-day period, or to start with the manufacturer’s values.

Then apply the previous estimate of SD to establish the control limits.

These control limits should be temporary, until sufficient data is collected to provide good estimates of both the mean and SD of the new material.

Establishing the Value of the Mean for a New Lot of QC Material

New lots of a quality control material should be analyzed for each analyte in parallel with the lot of control material in current use.

Ideally, a minimum of at least 20 measurements should be made on separate days when the measurement system is known to be stable, based on QC results from existing lots.

If the desired 20 data points from 20 days are not available, provisional values may have to be established from data collected over fewer than 20 days.

Possible approaches include making no more than four control measurements per day for five different days

Retained patients samples◦ Original samples must be assayed in the lab under accepted

control run conditions◦ Stored aliquited immediately after finishing 1st analysis◦ Storage conditions must meet the requirements for analytes to

be measured◦ Avoid repeated warming/ thawing◦ Stability of the measurand must be carefully respected◦ Better to be alternating with QC material◦ Result of the 1st assay is used as the base for comparison and

calculation (as if gold value)◦ Allowable analytical imprecision is used for judgment of

acceptance or rejection◦ Data calculated from biological variations/ CLIA limits are used

for the issue

When QC Material is deficient:

When QC Material is deficient: (cont.) Result comparison with an in-control

method/ instrument/ procedure for the measurand◦ The in-control instrument/ method is considered

the reference one◦ Not more than one hour time gap between the

parallel assays◦ Principles of assays must be considered if

different◦ Inaccuracy limits is used for comparison◦ Data calculated from biological variations/ CLIA

limits are used for the issue

Individual Patient Results:◦Clinical Correlations◦Correlation with other laboratory tests◦Intralaboratory duplicates◦Delta check with previous test results◦Limit Check

Multiple Patients:◦Test distribution statistics◦Monitoring patients means

Quality Control Using Patient Data

YOUR VALUABLE QUESTIONS