The document discusses internal quality control in clinical laboratories. It defines key terms like quality control, quality assurance, and quality management. It explains the importance of internal quality control in ensuring accurate and reliable test results. Quality control involves running control samples alongside patient samples and using statistical tools like control charts and Westgard rules to monitor the analytical process and ensure it is in control. Factors that could indicate the process is out of control are also summarized.

1. Internal Quality Control
Dr. Adel A. Elazab
Associate Professor of Clinical Pathology
Faculty of Medicine
Ain Shams University, Cairo, Egypt

3.  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.

4. STAGE ACTIVITIES PERFORMED
1. 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 objectives
4. QUALITY ASSURANCE Systematic activities to provide
“Confidence” that the organization
meets requirements for quality
5. QUALITY CONTROL Operational techniques applied to
“Specific Tasks” for quality and
regulatory compliance.

6.  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

7. 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

8. 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:-

9.  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.

10.  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

11.  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.

13. Organization
Customer Focus
Facilities and Safety
Personnel
Purchasing and Inventory
Equipment
Process Management
Pre-examination
Examination
Post-examination
Documents and Records
Information Management
Nonconforming Event Management
Assessments
Continual Improvement
Pree-xamination
Examination
Post-examination
Information 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

14. Laboratory Path of Workflow
Quality
System
Essentials
Organization
Personnel
Equipment
Purchasing/
Inventory
Process
Control
Documents/
Records
Occurrence
Management
Internal
Assessment
Process
Improvement
Service and
Satisfaction
Post Information
Preanalytical Analytical Analytical Management
Quality system essentials
apply 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

19. Lean

20.  Mega-Tools
◦ Lean
◦ Six Sigma
◦ Priority Matrices and
Risk Assessment
 Tools/Techniques
◦ Balanced Scorecards
◦ Brainstorming
◦ Control Charting
◦ Flow Charting
◦ Quality Indicators
◦ Surveys

21. ! Internal Quality Control (IQC)
Procedures
! External Quality Assessment
(EQA)
! Quality Management

22. ⇒ 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

23. Monitoring quality of laboratory testing,
accuracy and precision of laboratory
results

24.  Precise and
Inaccurate
 Precise and
Accurate

25.  Imprecise and
Inaccurate
 Imprecise and ??
Accurate

26.  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

27.  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.

28.  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

29.  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)

30.  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

31.  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

32. 1. 192 mg/dL
2. 194 mg/dL
3. 196 mg/dL
4. 196 mg/dL
5. 160 mg/dL
6. 196 mg/dL
7. 200 mg/dL
8. 200 mg/dL
9. 202 mg/dL
10. 255 mg/dL
11. 204 mg/dL
12. 208 mg/dL
13. 212 mg/dL

33. 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

34. 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

36.  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

37. Random Error (RE):
Imprecision
 Causes:
1. Pipetting error
2. Temperature error
3. Mixing defect
4. Machine need
troubleshooting
 Systematic Error
(SE): Inaccuracy
 Causes:
1. Deterioration of
control material
2. Deterioration of
calibrator
3. Deterioration of
reagents

38.  Allows determination of whether an analytical
run/s (in control) or (out of control)

53. October 1, 2008

54. October 1, 2008

56.  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

58.  Rejection rule = Out of control=
1. Stop testing
2. Identify and correct problem
3. Repeat testing on pt samples and
control
4. Don’t report pt results until problem
is solved and controls indicate proper
performance

59.  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.

60. 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.

61.  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

63.  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

64.  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

65.  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

66. YOUR VALUABLE QUESTIONS