EQAS Organization and
Management
Bibliography

• Fundamentals for External Quality
Assessment, IFCC/EMD/C-AQ, 1996
Uldall, A.; Wilding., P; Hill, P.
• External Quality Assessment in Clinical
Laboratories, J. C. Libeer, 1993
• Quality Assurance in Clinical Chemistry,
Scand. J. Clin. Lab. Invest. 47 (Suppl.
187), 1989 Uldall, A.
1998
EQAS Organization and
Management - IFCC/EMD/CAQ
1
¿What is an External Quality
Assessment Scheme (EQAS) ?
System designed to objectively assess
the quality of results obtained by
laboratories, by means of an external
agency
1998
EQAS Organization and
Management - IFCC/EMD/CAQ
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Functions of an EQAS
•Measures inter-laboratory variability
•Allows comparison and evaluation of methods,
reagents, instruments, etc
•Show laboratory performance
•Allows determinations of consensus values
•Investigate factors affecting quality, e.g. interferences
•Educational stimulus
•Element of third-part evaluation of laboratories for
licensing and accreditation
•Source for uncertainty calculation
1998
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Management - IFCC/EMD/CAQ
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Position of EQA
Quality Management
External Quality
Assessment
Quality Policy
Quality Assurance
GLP
Quality
Control
Internal Quality
Control
Other aspects of GLP
1998
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Management - IFCC/EMD/CAQ
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General cycle of an EQAS
Initial survey
EQAS send report
to participants
laboratories
General and
individually report
1998
Laboratory
Laboratory analyze
analyze
samples
samples
and
and send
send results
results
Statistical data
processing
EQAS Organization and
Management - IFCC/EMD/CAQ
Input and validation
of data results.
5
Education

EQA role in motivating through
• interpretation of reports
• general
• individuals
•
•
•
•
•
1998
discovering factors affecting quality
complementing internal quality control
calibration
preparation of quality control materials
quality assurance
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Management - IFCC/EMD/CAQ
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Types of EQA

Type 1
• Designed to document laboratory performance to a
third part: authorities, accreditation bodies, social
security, etc.

Type 2
• Designed to report analytical performance to
individual laboratories

Type 3
• Designed to support troubleshooting in laboratory.

Type 4
• Designed to evaluate methods of measurement and
IVD’s
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Management - IFCC/EMD/CAQ
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Important items in planning EQAS
•
•
•
•
•
•
•
•
•
How many laboratories are expected to participate
Budget
Specialties to work on
Geographic and climate characteristics
Type of control materials
Initial analytes to be investigated
How long the complete cycle will be
Forms design
How response of laboratory will be registered and
processed
• Availability of hardware and software
• Acceptability performance criteria
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Management - IFCC/EMD/CAQ
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International EQAS

Advantages
• Already planned
• Large number of
participants
• Allow more method
groups
1998

Disadvantages
• Low influence in the
EQAS design or
content
• Does not favor
development of
local experts
• Harder
communications
• Difficult to arrange
peer groups
• Often expensive
EQAS Organization and
Management - IFCC/EMD/CAQ
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National EQAS

Advantages
• System developed
according own needs
• Participants
communicate with
organizers more
directly
• Participants could
suggest modification
of the scheme
• Local expert
development
• Employment creation
1998

Disadvantages
• More management
work
• Greater budget
• Time consuming
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Management - IFCC/EMD/CAQ
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Sponsor Institution
• Assume the responsibility in front of the
community
• Transmit a clear image of the EEC
• Not to influence on the development of the
program
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Management - IFCC/EMD/CAQ
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Organizer: Desirable Profile
• High reputation among colleagues
• Commitment to a long term work
• Knowledge of the real situation were the
EQAS is intended to apply
• Deep knowledge of statistics
• Vision and diplomacy
• Independent of IVD-market supplier
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Management - IFCC/EMD/CAQ
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Logistics
• Adequate human resources
• Adequate resources to data
processing
• Preparation, acquisition and
distribution of control materials
• Print-shop service
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Management - IFCC/EMD/CAQ
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Types of EQAS according
activity
External assessment
only
 Combination External
assessment/Internal
Quality Control

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Management - IFCC/EMD/CAQ
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External Assessment only

Advantages
• Resources
concentration to
laboratory
standardization
• Freedom of
laboratories to
select their IQC
materials
1998

Disadvantages
• Very high cost of
individuals
laboratories to
get their IQC
materials
• Slow quality
improvement
EQAS Organization and
Management - IFCC/EMD/CAQ
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Combination EQA/IQC

Advantages
• All needs of
laboratories
covered.
• Maximal utilization
of EQA reports
• Unique code system
• Integration of EQA
and IQC data
1998

Disadvantage
• More work for the
organizer
• Greater widespread
of resources and
energy
• Huge administrative
work
EQAS Organization and
Management - IFCC/EMD/CAQ
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Financing

Free

• Advantages
• Advantages
• Facilitate participation
of all laboratories
• Simpler administration
• Central financing more
stable
• Disadvantages
• Seems that EQAS cost
nothing
• If central financing from
government, continuity is
tied to political changes
• Possible interference
from the financier
1998
Fee
• Participants realize the
real cost of the service
they receive
• Sense of belonging
• Allows programmed
expansion of the scheme
• Disadvantages
• If participation is not
mandatory, financing
could be unstable
• Greater administrative
work (invoicing)
• Discourage participation
EQAS Organization and
Management - IFCC/EMD/CAQ
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Participation

Mandatory

• Advantages
• Advantages
• The assessment
comprises all
laboratories
• More reliable data
• All patients receive the
benefits
• Disadvantages
• Does not guarantee
improvement
• Some participants does
not use the reports
1998
Voluntary
• System based in
professional
responsibility
• Participants are
interested in their
performance and
read/use reports
• Disadvantages
• The scheme get
competitors
• Only concerned
laboratories are
assessed
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Management - IFCC/EMD/CAQ
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Type of control materials
• Lyophilized animal serum
•
•
cheaper, good long term stability
important matrix effects for some constituents, reconstitution errors,
not appropriate for inmunologic tests
• Lyophilized human serum
•
•
More similar to patients specimens, good long term stability
Expensive, reconstitution errors, denaturation of proteins/lipoproteins
• Stabilized liquid serum
•
•
Ready to use, easy to prepare
Great matrix effects, less long term stability
• Freezed human serum
•
•
1998
ideal
Very expensive, difficult to obtain different level of concentration,
more unstable, storing and transport very expensive, danger of
contamination.
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Management - IFCC/EMD/CAQ
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Source of Control Materials
• Self prepared
• Commercial
• Custom problems
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Management - IFCC/EMD/CAQ
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Frequency of distributions

Low frequency

• Advantages
• Advantages
• Lower costs
• Less processing work
• Less requirement to the
participants
• Disadvantages
• Less statistical power
• Harder assessment
• Lower error detection
probability
1998
High frequency
• Better data-base
• Reliable assessment
• Better error detection
probability
• Disadvantages
• Greater expedition costs
• Greater costs in control
materials
• Greater costs to the
participant (reagents,
time, communications)
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Management - IFCC/EMD/CAQ
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Distribution: other factors
• Postal requirements for delivery of
biological materials
• Type, number and volume of materials to
be distributed
• Containers
• Labeling of samples
• Instructions
1998
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Management - IFCC/EMD/CAQ
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Reports

Concise

• Advantages
• Advantages
• Fast reading
• Fast and cheaper
production
• Disadvantages
• Limited information
• Abridged reports
require expertise to
be interpreted
1998
Detailed
• Much useful
information
• Participants receive
all information they
need
• Disadvantages
• Reading takes more
time
• Greater logistics
problems for design
and print
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Management - IFCC/EMD/CAQ
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Forms

Use

• Description of
analytical
characteristics
(codes)
• Changes in
analytical
characteristics
• Report of results
1998

Easy to understand
Need to have
• Laboratory code
• Reception of
samples date
• Analysis date
• Duplicate for the
laboratory
• Design with the help
of programmers and
operators
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Management - IFCC/EMD/CAQ
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Instructions to the
participants
•
•
•
•
Scope of the scheme
Needs of regular participation
How the results are assessed
Follow instructions to fill forms (units,
method info, etc)
• Adequately answer questions from the
organizer
• How and to whom ask for help
1998
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Management - IFCC/EMD/CAQ
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Optimal criteria for EQAS
design
• Scientific validity
• reliable control materials
• valid assigned values
• valid statistical treatment
• Reliability
•
•
•
•
•
•
1998
confidentiality
frequent distributions
short cycle
intelligible reports
strictly execution of the schedule
scoring system
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Management - IFCC/EMD/CAQ
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