oSIST prEN ISO 20776-2:2021

Clinical laboratory testing and in vitro diagnostic test systems - Susceptibility testing of infectious agents and evaluation of performance of antimicrobial susceptibility test - Part 2: Evaluation of performance of antimicrobial susceptibility test devices against reference broth micro-dilution (ISO/DIS 20776-2:2021)

Resolution BT C87/2011 (extension of DOW): DOW = DAV + 36 months

Labormedizinische Untersuchungen und In-vitro-Diagnostika-Systeme - Empfindlichkeitsprüfung von Infektionserregern und Evaluation von Geräten zur antimikrobiellen Empfindlichkeitsprüfung - Teil 2: Evaluation der Leistung einer Vorrichtung zur antimikrobiellen Empfindlichkeitsprüfung (ISO/DIS 20776-2:2021)

Dieses Dokument legt annehmbare Leistungskriterien für Testsysteme zur Prüfung der mikrobiellen Empfindlichkeit (AST, en: antimicrobial susceptibility test) fest, die zur Bestimmung der minimalen Hemmkonzentrationen (MHK) von Bakterien auf antimikrobielle Substanzen in medizinischen Laboren verwendet werden.
Dieses Dokument legt Anforderungen an Testsysteme zur Prüfung der mikrobiellen Empfindlichkeit sowie Verfahren zur Leistungsbewertung dieser Testsysteme fest. Es legt fest, wie eine Leistungsbewertung eines Testsystems zur Prüfung der mikrobiellen Empfindlichkeit durchzuführen ist.
Dieses Dokument wurde mit dem Ziel erarbeitet, Hersteller bei der Durchführung von Leistungsbewertungs-studien anzuleiten.

Systèmes d’essais en laboratoire et de diagnostic in vitro - Sensibilité in vitro des agents infectieux et évaluation des performances des dispositifs pour antibiogrammes - Partie 2 : Évaluation des performances des dispositifs pour antibiogrammes contre méthode de référence de microdilution en bouillon (ISO/DIS 20776-2:2021)

Klinični laboratorijski preskusi ter diagnostični preskusni sistemi in-vitro - Preskus občutljivosti povzročiteljev infekcij in vrednotenje delovanja antimikrobno občutljivih preskusnih naprav - 2. del: Vrednotenje delovanja antimikrobno občutljivih naprav (ISO/DIS 20776-2:2021)

General Information

• Status: Not Published
• Public Enquiry End Date: 19-Jul-2021
• ICS: 11.100.10 - In vitro diagnostic test systems
• ICS: 11.100.20 - Biological evaluation of medical devices
• Technical Committee: VAZ - Healthcare
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 12-May-2021
• Due Date: 29-Sep-2021
• Completion Date: 04-Jun-2021
• Ref Project: prEN ISO 20776-2 - Clinical laboratory testing and in vitro diagnostic test systems - Susceptibility testing of infectious agents and evaluation of performance of antimicrobial susceptibility test - Part 2: Evaluation of performance of antimicrobial susceptibility test devices against reference broth micro-dilution (ISO/DIS 20776-2:2021)

RELATIONS

• Revised: SIST EN ISO 20776-2:2008 - Clinical laboratory testing and in vitro diagnostic test systems - Susceptibility testing of infectious agents and evaluation of performance of antimicrobial susceptibility test devices - Part 2: Evaluation of performance of antimicrobial susceptibility test devices (ISO 20776-2:2007)
• Effective Date: 01-Jul-2021

Standards Content (sample)

SLOVENSKI STANDARD
oSIST prEN ISO 20776-2:2021
01-julij-2021
Klinični laboratorijski preskusi ter diagnostični preskusni sistemi in-vitro -

Preskus občutljivosti povzročiteljev infekcij in vrednotenje delovanja antimikrobno

občutljivih preskusnih naprav - 2. del: Vrednotenje delovanja antimikrobno
občutljivih naprav (ISO/DIS 20776-2:2021)

Clinical laboratory testing and in vitro diagnostic test systems - Susceptibility testing of

infectious agents and evaluation of performance of antimicrobial susceptibility test - Part

2: Evaluation of performance of antimicrobial susceptibility test devices against reference

broth micro-dilution (ISO/DIS 20776-2:2021)
Labormedizinische Untersuchungen und In-vitro-Diagnostika-Systeme -
Empfindlichkeitsprüfung von Infektionserregern und Evaluation von Geräten zur
antimikrobiellen Empfindlichkeitsprüfung - Teil 2: Evaluation der Leistung einer
Vorrichtung zur antimikrobiellen Empfindlichkeitsprüfung (ISO/DIS 20776-2:2021)

Systèmes d’essais en laboratoire et de diagnostic in vitro - Sensibilité in vitro des agents

infectieux et évaluation des performances des dispositifs pour antibiogrammes - Partie 2

: Évaluation des performances des dispositifs pour antibiogrammes contre méthode de

référence de microdilution en bouillon (ISO/DIS 20776-2:2021)
Ta slovenski standard je istoveten z: prEN ISO 20776-2
ICS:
11.100.10 Diagnostični preskusni In vitro diagnostic test
sistemi in vitro systems
oSIST prEN ISO 20776-2:2021 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 20776-2:2021
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oSIST prEN ISO 20776-2:2021
DRAFT INTERNATIONAL STANDARD
ISO/DIS 20776-2
ISO/TC 212 Secretariat: ANSI
Voting begins on: Voting terminates on:
2021-04-30 2021-07-23
Clinical laboratory testing and in vitro diagnostic
test systems — Susceptibility testing of infectious
agents and evaluation of performance of antimicrobial
susceptibility test —
Part 2:
Evaluation of performance of antimicrobial susceptibility
test devices against reference broth micro-dilution
ICS: 11.100.20
THIS DOCUMENT IS A DRAFT CIRCULATED
This document is circulated as received from the committee secretariat.
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
ISO/CEN PARALLEL PROCESSING
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 20776-2:2021(E)
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION. ISO 2021
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oSIST prEN ISO 20776-2:2021
ISO/DIS 20776-2:2021(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2021

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may

be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting

on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address

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ISO copyright office
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Published in Switzerland
ii © ISO 2021 – All rights reserved
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oSIST prEN ISO 20776-2:2021
ISO/DIS 20776-2:2021(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction ................................................................................................................................................................................................................................vi

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Test methods ............................................................................................................................................................................................................. 5

4.1 General ........................................................................................................................................................................................................... 5

4.2 Methods ......................................................................................................................................................................................................... 6

4.2.1 Reference method ........................................................................................................................................................... 6

4.2.2 Strain selection .................................................................................................................................................................. 6

4.2.3 Quality control (QC) ...................................................................................................................................................... 6

4.2.4 Quality control (QC) of the reference method ........................................................................................ 7

4.2.5 Reproducibility testing of test device ............................................................................................................ 7

4.2.6 Isolate testing protocol ............................................................................................................................................... 7

4.2.7 Inoculum preparation ................................................................................................................................................. 7

4.2.8 Discrepancy resolution testing ............................................................................................................................ 7

4.2.9 System under evaluation .......................................................................................................................................... 8

5 Data analysis and acceptance criteria ............................................................................................................................................ 8

5.1 Accuracy of test device ..................................................................................................................................................................... 8

5.1.1 General...................................................................................................................................................................................... 8

5.1.2 MIC devices ........................................................................................................................................................................... 8

5.1.3 Qualitative AST devices ............................................................................................................................................. 8

5.2 Quality control of test device ...................................................................................................................................................... 9

5.3 Reproducibility of test device..................................................................................................................................................... 9

5.4 Documents related to study ......................................................................................................................................................... 9

Annex A (informative) Evaluating the performance of MIC tests .........................................................................................10

Annex B (informative) Rationale for bias analysis ..............................................................................................................................13

Annex C (informative) Sensitivity and specificity analyses for qualitative tests .................................................15

Bibliography .............................................................................................................................................................................................................................17

© ISO 2021 – All rights reserved iii
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oSIST prEN ISO 20776-2:2021
ISO/DIS 20776-2:2021(E)
Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards

bodies (ISO member bodies). The work of preparing International Standards is normally carried out

through ISO technical committees. Each member body interested in a subject for which a technical

committee has been established has the right to be represented on that committee. International

organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.

ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of

electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of

any patent rights identified during the development of the document will be in the Introduction and/or

on the ISO list of patent declarations received (see www .iso .org/ patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and

expressions related to conformity assessment, as well as information about ISO's adherence to the

World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso .org/

iso/ foreword .html.

This document was prepared by Technical Committee ISO/TC 212, Clinical laboratory testing and in

vitro diagnostic test systems.

This document cancels and replaces the first edition (ISO 20776-2:2007), which has been technically

revised.
The main changes compared to the previous edition are as follows:
— Revision in the title of part 2 to better align with the intended information;
— Addition of an Introduction – not presented in the original version.
— Revised Terms and Definitions as follows:

— Removed definitions for Category agreement, susceptible, intermediate, resistant, non-susceptible,

major discrepancy, minor discrepancy, very major discrepancy, breakpoint test, zone diameter;

— Added definition for contemporary isolate and removed definitions for fresh isolate, recent isolate;

— Added definitions for reproducibility, bias of the test method, sensitivity analysis, specificity

analysis, organism group;

— Added definition for qualitative test and removed definition for breakpoint test;

— Revised definitions for minimum inhibitory concentration test, breakpoint, quality control,

discrepancy;

— Moved general requirements for a performance evaluation as a separate section, to the overview

(now renamed general section) under test methods;
— Reordered Test methods section;

— Revised quality control section, and referenced EUCAST and CLSI documents for quality control

ranges;
iv © ISO 2021 – All rights reserved
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oSIST prEN ISO 20776-2:2021
ISO/DIS 20776-2:2021(E)
— Revised reference method section to add variability;

— Revised strain selection section and incorporated new definition of contemporary isolates;

— Revised reproducibility testing section;
— Revised discrepancy resolution section;
— Combined data analysis and acceptance criteria sections;
— Revised Accuracy of test device section to remove category agreement;

— Revised data analysis for MIC devices to remove category agreement. Added bias requirement;

— Removed acceptance for breakpoint AST devices;

— Added section for acceptance criteria for qualitative AST devices and included sensitivity and

specificity requirements;

— Revised sections for quality control of test device and reproducibility of test device;

— Revised bibliography;

— Added Annexes A - Evaluation the Performance of MIC Tests, B - Rationale for Bias Analysis, and

Annex C - Sensitivity and Specificity Analyses for Qualitative Tests
A list of all parts in the ISO 20776 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www .iso .org/ members .html.
© ISO 2021 – All rights reserved v
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oSIST prEN ISO 20776-2:2021
ISO/DIS 20776-2:2021(E)
Introduction

In vitro antimicrobial susceptibility tests are performed on micro-organisms suspected of causing

disease, particularly if the organism is thought to belong to a species that may exhibit resistance

to frequently used antimicrobial agents. The tests are also important in resistance surveillance,

epidemiological studies of susceptibility and in comparisons of new and existing agents.

Dilution procedures are used to determine the minimum inhibitory concentrations (MICs) of

antimicrobial agents for antimicrobial susceptibility testing. MIC methods are used in resistance

surveillance, defining and identifying wild type phenotypes, comparative testing of new agents,

to establish the susceptibility of organisms that give equivocal results in routine tests, for tests on

organisms where routine tests may be unreliable and when a quantitative result is required for clinical

management. In dilution tests, micro-organisms are tested for their ability to produce visible growth in

broth (broth dilution) containing serial dilutions of the antimicrobial agent or on a series of agar plates

(agar dilution).

The lowest concentration of an antimicrobial agent (in mg/l) that, under defined in vitro conditions,

prevents the appearance of visible growth of a micro-organism within a defined period of time is

known as the MIC. Careful control and standardization are required for intra- and inter-laboratory

reproducibility of broth MIC tests. The MICs of quality control strains generally span three doubling

dilutions with a dominant central value, but may have a four-dilution range.

Broth micro-dilution denotes the performance of the broth dilution test in micro-dilution trays.

Broth micro-dilution is now one of the most common methods used globally to perform antimicrobial

susceptibility tests.

This document is a revision of a previous ISO document (ISO 20776-2: 2007, Clinical laboratory

testing and in vitro diagnostic test systems — Susceptibility testing of infectious agents and evaluation

of performance of antimicrobial susceptibility test devices — Part 2: Evaluation of performance of

antimicrobial susceptibility test devices). The document is designed for the evaluation of antimicrobial

test devices against the standard broth micro-dilution reference method (ISO 20776-1:2019) using

pure cultures of aerobic bacteria that are easily grown by overnight incubation on agar and grow well

in standardized micro-dilution trays containing standardized Mueller-Hinton broth (volume of ≤200

µl), which may need to be modified depending on the antimicrobial agent being tested.

Quantitative MIC and qualitative evaluations detailed in this revised document measure the accuracy,

reproducibility, and quality control of tests performed with antimicrobial test devices that generate MIC

values against the standard broth micro-dilution reference method. Antimicrobial agar disc diffusion

tests are not included in this revision.

This document has been revised using the premise that the MIC test is an in vitro assay, subject to intra-

and interlaboratory assay variation. When making the comparison between any derivative test and that

of the reference method, it is appropriate to apply measures of assay performance only and not result

interpretation. For this reason, and because interpretive categories were removed from the revision

of the companion document ISO 20776-1, categorical agreement (CA) and its associated terminology,

as described by the U.S. Food and Drug Administration (FDA), the Clinical and Laboratory Standards

Institute (CLSI) M23 document, and other international documents, has not been applied. Avoiding an

assessment of CA also assists in reducing the requirement to reassess assay performance automatically

when the only change has been a breakpoint change (which is external to the assay itself).

This document applies to new performance evaluations initiated after the acceptance date of the

standard; studies conducted prior to the acceptance date of this document may not need to be re-

designed and/or re-analysed using these criteria. Studies conducted prior to these standards or

acceptance of this document follow standard practice or guidance at the time of the study.

For derivative tests with more than 3 two-fold dilutions, assay performance is assessed with tools

designed to measure accuracy using Essential Agreement (EA) and bias, and precision using EA only.

For derivative tests with 1-3 concentrations, assay performance is assessed using standard sensitivity

and specificity measures.
vi © ISO 2021 – All rights reserved
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oSIST prEN ISO 20776-2:2021
DRAFT INTERNATIONAL STANDARD ISO/DIS 20776-2:2021(E)
Clinical laboratory testing and in vitro diagnostic
test systems — Susceptibility testing of infectious
agents and evaluation of performance of antimicrobial
susceptibility test —
Part 2:
Evaluation of performance of antimicrobial susceptibility
test devices against reference broth micro-dilution
1 Scope

This document establishes acceptable performance criteria for antimicrobial susceptibility test

(AST) devices that are used to determine minimum inhibitory concentrations (MIC) of bacteria to

antimicrobial agents in medical laboratories.

This document specifies requirements for AST devices and procedures for assessing performance of

such devices. It defines how a performance evaluation of an AST device is to be conducted.

This document has been developed to guide manufacturers in the conduct of performance evaluation

studies.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any amendments) applies.

ISO 20776-1:2019, Susceptibility testing of infectious agents and evaluation of performance of antimicrobial

susceptibility test devices — Part 1: Broth micro-dilution reference method for testing the in vitro activity

of antimicrobial agents against rapidly growing aerobic bacteria involved in infectious diseases

3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
antimicrobial susceptibility test device
AST device

device including all specified components used to obtain test results that allow MIC determination of

bacteria with specific antimicrobial agents

Note 1 to entry: Specific components of the device include inoculators, disposables and reagents, media used

to perform the test, and readers. Non-specific components, such as swabs, pipettes and tubes, are not part of

the device.
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oSIST prEN ISO 20776-2:2021
ISO/DIS 20776-2:2021(E)
3.2
reference method

reference method described in ISO 20776-1 most recent version. This reference method describes

dilution procedures to determine the minimum inhibitory concentration of antimicrobial agents

3.3
minimum inhibitory concentration
MIC

lowest concentration that, under defined in vitro conditions, prevents visible growth of bacteria within

a defined period of time
Note 1 to entry: The MIC is expressed in mg/l.
3.4
minimum inhibitory concentration test
MIC test

test that is capable of determining an MIC [3.3] covering a range of at least four consecutive doubling

dilutions, and for which Essential Agreement (EA) can be determined
3.4.1
on-scale MIC test result

result from a MIC test [3.4] when there is growth in at least one dilution below the MIC endpoint and no

growth in at least one dilution above
3.5
breakpoint

specific values of parameters, such as MICs [3.3], on the basis of which bacteria can be assigned to

clinical categories such as “susceptible” (S) or “resistant” (R)

Note 1 to entry: For current interpretive breakpoints and interpretive categories, reference should be made to

the latest publications of organizations employing this reference method [3.2] (e.g., CLSI(1) and EUCAST(2)).

3.6
qualitative test

test that has the principal objective to provide a qualitative result (e.g., using a breakpoint [3.5] or

screening concentration)
Note 1 to entry: Such tests have a limited range of 1-3 doubling dilutions.
3.7
quality control of antimicrobial susceptibility tests

quality control includes the use of carefully selected bacterial strains with given expected MIC [3.3] results

Note 1 to entry: MICs [3.3] of antimicrobial agents for control organisms should be within the ranges given in

[1] [3]

the latest versions of the CLSI M100 document or the EUCAST Quality Control document. It is not possible to

provide a single Quality Control Table.
3.8
reproducibility

extent to which consistent results such as MICs are obtained when the test is repeated

3.9
evaluation of test results
3.9.1
discrepancy

difference in a result between the test method (either a MIC test [3.4] or a qualitative test [3.6]) and

the reference method [3.2] (ISO 20776-1) outside the region of essential agreement (MIC test [3.4]), or

outside the region of sensitivity and specificity (qualitative test [3.6])
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ISO/DIS 20776-2:2021(E)
3.9.2
essential agreement

MIC [3.3] result obtained with the AST device [3.1] that is within plus or minus one two-fold dilution

step from the MIC [3.3] value established with the reference method [3.2] (ISO 20776-1)

Note 1 to entry: Used for MIC [3.3] devices.
Note 2 to entry: Another representation of the concept is:
×100 , where:

N is the number of bacterial isolates with an EA;N is the total number of bacterial isolates tested

Note 3 to entry: The overall EA is expressed as a percentage.
3.9.3
bias of the test method

evaluation of test device results to determine whether the results that differ from the reference method

[3.2] are significantly skewed or predominantly in one direction
Note 1 to entry: Used for MIC tests [3.4].
3.9.4.1
sensitivity analysis

measure of agreement between test device results and reference

method [3.2] results that are positive or above a published breakpoint [3.5] Can also be considered as

positive percent agreement when reference results are interpreted as positive
Note 1 to entry: Used for qualitative tests [3.6].
Note 2 to entry: See Table 1 .
Table 1 — Sensitivity analysis for a qualitative (screening or breakpoint) test
Reference method
Total
(-) or no growth (+) or growth
(-) or no growth a b a+b
Test method
(+) or growth c d c+d
Total a+c b+d Sum of (a,b,c,d)
Sensitivity = 100×÷db()+d
3.9.4.2
sensitivity analysis

measure of agreement between test device results and reference

method [3.2] results that have the MICs [3.3] at the high end of the scale
Note 1 to entry: Used for qualitative tests [3.6].
Note 2 to entry: See Table 2 .
Table 2 — Sensitivity analysis for a three-dilution qualitative test
Reference method
Total
≤ Low MIC Middle MIC ≥ High MIC
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Table 2 (continued)
≤ Low MIC a b c a+b+c
Test method Middle MIC d e f d+e+f
≥ High MIC g h i g+h+i
Total a+d+g b+e+h c+f+i Sum of (a to i))
Sensitivity = 100×÷ic()++fi
3.9.5.1
specificity analysis

measure of agreement between test device results and reference

method [3.2] results that are negative or below a published breakpoint [3.5] Can also be considered as

negative percent agreement when reference results are interpreted as negative
Note 1 to entry: Used for qualitative tests [3.6].
Note 2 to entry: See Table 3 .
Table 3 — Specificity analysis for a qualitative (screening or breakpoint) test
Reference method
Total
(-) or no growth (+) or growth
(-) or no growth a b a+b
Test method
(+) or growth c d c+d
Total a+c b+d Sum of (a,b,c,d)
Specificity = 100×÷aa()+c
3.9.5.2
specificity analysis

measure of agreement between test device results and reference

method [3.2] results that have the MICs [3.3] at the low end of the scale
Note 1 to entry: Used for qualitative tests [3.6].
Note 2 to entry: See Table 4 .
Table 4 — Specificity analysis for a three-dilution qualitative test
Reference method
Total
≤ Low MIC Middle MIC ≥ High MIC
≤ Low MIC a b c a+b+c
Test method Middle MIC d e f d+e+f
≥ High MIC g h i g+h+i
Total a+d+g b+e+h c+f+i Sum of (a to i))
Specificity = 100×÷aa()++dg
3.10.1
contemporary isolate

isolate recovered from a clinical sample within the previous six months that has been minimally sub-

cultured

Note 1 to entry: Ideally, they are consecutive and prospectively collected. These isolates can have been frozen

prior to use.
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3.10.2
stock isolate

isolate recovered from a clinical sample that has been retained, stored or obtained from a culture

collection

Note 1 to entry: Stock isolates are usually included because they have known or rare resistance mechanisms

or are of a genus or species for which the antimicrobial agent is indicated but are not commonly isolated. Such

organisms are unlikely to be available in contemporary isolates used in the evaluation. There is no requirement

for how long ago the isolate was obtained.
3.11
coordinator

person empowered by the manufacturer or investigator [3.12] with responsibility for the entire

performance evaluation
3.12
investigator

person responsible for the execution of the performance evaluation at a certain location

3.13
evaluation plan
description of a planned performance evaluation
3.14
evaluation report
description of and conclusions from a performance evaluation
3.15
organism group
group of related micro-organisms that share similar characteristics
4 Test methods
4.1 General

The manufacturer or investigator takes the responsibility for the initiation and the conduct of

a performance evaluation according to the evaluation plan. The manufacturer shall define the

responsibility and the interrelation of all personnel who manage and conduct a performance evaluation.

The manufacturer or investigator shall appoint a coordinator with overall responsibility for the

performance evaluation and the evaluation report. This may include a coordinator, who shall assess

and document criteria used and indicate which performance claims are met.

An evaluation conducted by a manufacturer shall consist of accuracy using contemporary and stock

strains, reproducibility and quality control testing performed in at least three different laboratories,

of which a maximum of one may be the manufacturer's laboratory. Alternatively, these studies may

be conducted at a single site that mimics three sites (e.g., multiple users/instruments, geographically

diverse source of organisms. This single site may be within the manufacturer’s laboratory. The complete

testing protocol should focus on the m
...