1998 EQAS Organization and Management - IFCC/EMD/C- AQ1 EQAS Organization and Management l Bibliography Fundamentals for External Quality Assessment, IFCC/EMD/C-AQ,

1998 EQAS Organization and Management - IFCC/EMD/C-AQ

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EQAS Organization and Management

Bibliography• Fundamentals for External Quality

Assessment, IFCC/EMD/C-AQ, 1996Uldall, 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.


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¿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


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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 forlicensing and accreditation•Source for uncertainty calculation


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Position of EQA

Quality Management

Quality Policy

Quality Assurance GLP

Quality Control

Internal Quality Control

External QualityAssessment

Other aspects of GLP


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General cycle of an EQAS

Initial survey

Laboratory analyze samples

and send results

Input and validation of data results.Statistical data

processing

General and individually report

EQAS send report to participants laboratories


and send results


and send results


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Education

EQA role in motivating through • interpretation of reports

• general• individuals

• discovering factors affecting quality• complementing internal quality control• calibration• preparation of quality control materials• quality assurance


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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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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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International EQAS

Advantages• Already planned• Large number of

participants• Allow more method

groups

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


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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

Disadvantages• More management work• Greater budget• Time consuming


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• Assume the responsibility in front of the community • Transmit a clear image of the EEC • Not to influence on the development of the program

Sponsor Institution


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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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Logistics

• Adequate human resources• Adequate resources to data

processing• Preparation, acquisition and

distribution of control materials• Print-shop service


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Types of EQAS according activity

External assessment only Combination External

assessment/Internal Quality Control


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External Assessment only

Advantages• Resources

concentration to laboratory standardization

• Freedom of laboratories to select their IQC materials

Disadvantages• Very high cost of

individuals laboratories to get their IQC materials

• Slow quality improvement


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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

Disadvantage• More work for the

organizer• Greater widespread of

resources and energy• Huge administrative

work


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Financing

Free• 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

Fee• Advantages

• 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


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Participation

Mandatory• 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

Voluntary• Advantages

• 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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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• ideal• Very expensive, difficult to obtain different level of concentration, more

unstable, storing and transport very expensive, danger of contamination.


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Source of Control Materials

•Self prepared•Commercial

• Custom problems


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Frequency of distributions

Low frequency• Advantages

• Lower costs• Less processing work• Less requirement to the

participants

• Disadvantages• Less statistical power• Harder assessment• Lower error detection

probability

High frequency• Advantages

• 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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Distribution: other factors

• Postal requirements for delivery of biological materials

• Type, number and volume of materials to be distributed

• Containers• Labeling of samples• Instructions


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Reports

Concise• Advantages

• Fast reading• Fast and cheaper

production

• Disadvantages• Limited information• Abridged reports

require expertise to be interpreted

Detailed • Advantages

• 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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Forms

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

Use• Description of

analytical characteristics (codes)

• Changes in analytical characteristics

• Report of results


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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


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Optimal criteria for EQAS design

• Scientific validity• reliable control materials• valid assigned values• valid statistical treatment

• Reliability• confidentiality• frequent distributions• short cycle• intelligible reports• strictly execution of the schedule• scoring system

Documents

1998 EQAS Organization and Management - IFCC/EMD/C- AQ1 EQAS Organization and Management l Bibliography Fundamentals for External Quality Assessment, IFCC/EMD/C-AQ,