SIST EN ISO 20186-3:2020

Molecular in-vitro diagnostic examinations - Specifications for pre-examination processes for venous whole blood - Part 3: Isolated circulating cell free DNA from plasma (ISO 20186-3:2019)

This International Standard recommends the handling, documentation, storage and processing of venous whole blood specimens intended for circulating cell free DNA (ccfDNA) examination during the pre-examination phase before a molecular assay is performed. This International Standard covers specimens collected in venous whole blood collection tubes. This International Standard is applicable to molecular in vitro diagnostic examinations including laboratory developed tests performed by medical laboratories. It is also intended to be used by laboratory customers, in vitro diagnostics developers and manufacturers, but also pertains institutions and commercial organizations performing biomedical research, biobanks, and regulatory authorities.
CcfDNA profiles can change significantly after blood collection from the donor (e.g., release of genomic DNA from white blood cells, ccfDNA fragmentation and ccfDNA quantity change). Therefore, special measures have to be taken to secure good quality blood samples for ccfDNA examination and storage.
Different dedicated measures need to be taken for preserving blood genomic DNA, which are not described in this International Standard. Blood genomic DNA is covered in ISO 20185-2, Molecular in vitro diagnostic examinations — specifications for pre-examination processes for venous whole blood — Part 2: Isolated genomic DNA.
NOTE         CcfDNA obtained from blood by the procedures suggested in this document can contain DNA present in exosomes.
Pathogen DNA present in blood is not covered by this International Standard.
Different dedicated measures need to be taken for preserving DNA in circulating exosomes, which are not described in this International Standard.
NOTE   International, national or regional regulations or requirements may also apply to specific topics covered in this International Standard.

Molekularanalytische in-vitro-diagnostische Verfahren - Spezifikationen für präanalytische Prozesse für venöse Vollblutproben - Teil 3: Aus Plasma isolierte zirkulierende zellfreie DNS (ISO 20186-3:2019)

Dieses Dokument enthält Empfehlungen und Anforderungen für die Handhabung, Lagerung, Verarbeitung und Dokumentation von venösen Vollblutproben, die für die Untersuchung zirkulierender zellfreier DNA (ccfDNA) vorgesehen sind, während der präanalytischen Phase vor Beginn einer analytischen Prüfung. Dieses Dokument behandelt Untersuchungsmaterial, das in Blutentnahmeröhrchen für venöses Vollblut entnommen wurde.
Dieses Dokument gilt für alle molekularen in vitro diagnostischen Untersuchungen, die in medizinischen Laboren durchgeführt werden. Es ist außerdem auch für die Verwendung durch Labor Kunden, Entwickler und Hersteller von In vitro Diagnostika, Biobanken, Einrichtungen und kommerzielle Organisationen, die in der biomedizinischen Forschung tätig sind, sowie durch Aufsichtsbehörden vorgesehen.
Zur Stabilisierung genomischer DNA aus Blut werden andere spezielle Maßnahmen getroffen, die nicht in diesem Dokument beschrieben sind. Genomische DNA aus Blut wird in ISO 20186 2 behandelt.
Zur Erhaltung der DNA in zirkulierenden Exosomen werden andere zweckbestimmte Maßnahmen ergriffen, die in diesem Dokument nicht beschrieben werden.
ANMERKUNG   ccfDNA, die mit den in diesem Dokument vorgeschlagenen Verfahren aus Blut gewonnen wurde, kann DNA enthalten, die ursprünglich in Exosomen vorlag [8], [9].
Nicht durch dieses Dokument abgedeckt ist DNA, die in Krankheitserregern im Blut vorhanden ist.

Tests de diagnostic moléculaire in vitro - Spécifications relatives aux processus pré-analytiques pour le sang - ARN cellulaire - Partie 3: ADN libre circulant extrait du plasma (ISO 20186-3:2019)

Le présent document fournit des recommandations et des exigences sur la manipulation, le stockage, le traitement et la documentation des prélèvements de sang total veineux destinés à l'analyse de l'ADN libre circulant (ADNlc) durant la phase préanalytique précédant la réalisation d'un essai analytique. Le présent document concerne les échantillons primaires prélevés dans des tubes de prélèvement de sang total veineux.
Le présent document s'applique aux analyses de diagnostic moléculaire in vitro réalisées par des laboratoires de biologie médicale. Il est également destiné à être utilisé par des clients de laboratoires, des développeurs et fabricants de l'industrie du diagnostic in vitro, ainsi que par des biobanques, des institutions et des organismes commerciaux spécialisés en recherche biomédicale, de même que des autorités de réglementation.
Des mesures spécifiques différentes, non décrites dans le présent document, sont prises pour stabiliser l'ADN génomique sanguin. L'ADN génomique sanguin est couvert par l'ISO 20186-2.
Des mesures spécifiques différentes, non décrites dans le présent document, sont prises pour préserver l'ADN des exosomes circulants.
NOTE       L'ADNlc extrait du sang à l'aide des protocoles cités dans le présent document est susceptible de contenir de l'ADN présent à l'origine dans les exosomes[8][9].
L'ADN des pathogènes présents dans le sang n'est pas couvert par le présent document.

Molekularne diagnostične preiskave in vitro - Specifikacije za predpreiskovalne procese za vensko polno kri - 3. del: Iz plazme izolirana cirkulirajoča brezcelična DNK (ISO 20186-3:2019)

Ta mednarodni standard vsebuje priporočila za obravnavo, dokumentiranje, shranjevanje in obdelavo vzorcev venske polne krvi, namenjenih za analizo cirkulirajoče brezcelične DNK (ccfDNA) med predpreiskovalno fazo, preden se izvede molekularni preskus. Ta mednarodni standard zajema vzorce, ki so zbrani s cevkami za zbiranje venske polne krvi. Ta mednarodni standard se uporablja za molekularne diagnostične preiskave in vitro, vključno z laboratorijsko razvitimi preskusi, ki jih izvajajo v medicinskih laboratorijih. Uporabljali naj bi ga tudi uporabniki laboratorijev, razvijalci in proizvajalci diagnostike in vitro, navezuje pa se tudi na institucije in komercialne organizacije, ki izvajajo biomedicinske raziskave, biobanke ter regulativne organe. Profili cirkulirajoče brezcelične DNK se lahko znatno spremenijo po odvzemu krvi od darovalca (npr. sprostitev genomske DNK iz belih krvnih celic, razpad ali sprememba količine cirkulirajoče brezcelične DNK). Zato je treba sprejeti posebne ukrepe za pridobivanje vzorcev krvi dobre kakovosti za analizo in shrambo cirkulirajoče brezcelične DNK. Za ohranjanje krvne genomske DNK je treba uporabiti drugačne namenske ukrepe, ki niso opisani v tem mednarodnem standardu. Krvna genomska DNK je opisana v standardu ISO 20185-2, Molekularne diagnostične preiskave in vitro – specifikacije za predpreiskovalne procese za vensko polno kri - 2. del: Iz genoma izolirana DNK OPOMBA: cirkulirajoča brezcelična DNK iz krvi, pridobljena s postopki, ki jih predlaga ta dokument, lahko vsebuje DNK iz eksosomov. Patogena DNK v krvi ni zajeta v tem mednarodnem standardu. Za ohranjanje DNK v cirkulirajočih eksosomih je treba uporabiti drugačne namenske ukrepe, ki niso opisani v tem mednarodnem standardu. OPOMBA: Za določene teme, ki so zajete v tem mednarodnem standardu, lahko veljajo tudi mednarodni, nacionalni ali regionalni predpisi ali zahteve.

General Information

• Status: Published
• Public Enquiry End Date: 19-Mar-2018
• Publication Date: 10-Dec-2019
• ICS: 11.100.10 - In vitro diagnostic test systems
• Technical Committee: VAZ - Healthcare
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 20-Nov-2019
• Due Date: 25-Jan-2020
• Completion Date: 11-Dec-2019
• Ref Project: EN ISO 20186-3:2019 - Molecular in-vitro diagnostic examinations - Specifications for pre-examination processes for venous whole blood - Part 3: Isolated circulating cell free DNA from plasma (ISO 20186-3:2019)

Relations

• Replaces: SIST-TS CEN/TS 16835-3:2015 - Molecular in vitro diagnostic examinations - Specifications for pre-examination processes for venous whole blood - Part 3: Isolated circulating cell free DNA from plasma
• Effective Date: 01-Jan-2020
• Replaces: SIST-TS CEN/TS 16835-3:2015 - Molecular in vitro diagnostic examinations - Specifications for pre-examination processes for venous whole blood - Part 3: Isolated circulating cell free DNA from plasma
• Effective Date: 08-Jun-2022

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 20186-3:2020
01-januar-2020
Nadomešča:
SIST-TS CEN/TS 16835-3:2015
Molekularne diagnostične preiskave in vitro - Specifikacije za predpreiskovalne
procese za vensko polno kri - 3. del: Iz plazme izolirana cirkulirajoča brezcelična
DNK (ISO 20186-3:2019)
Molecular in-vitro diagnostic examinations - Specifications for pre-examination processes
for venous whole blood - Part 3: Isolated circulating cell free DNA from plasma (ISO
20186-3:2019)
Molekularanalytische in-vitro-diagnostische Verfahren - Spezifikationen für
präanalytische Prozesse für venöse Vollblutproben - Teil 3: Aus Plasma isolierte
zirkulierende zellfreie DNS (ISO 20186-3:2019)
Tests de diagnostic moléculaire in vitro - Spécifications relatives aux processus pré-
analytiques pour le sang - ARN cellulaire - Partie 3: ADN libre circulant extrait du plasma
(ISO 20186-3:2019)
Ta slovenski standard je istoveten z: EN ISO 20186-3:2019
ICS:
11.100.10 Diagnostični preskusni In vitro diagnostic test
sistemi in vitro systems
SIST EN ISO 20186-3:2020 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 20186-3:2020


EN ISO 20186-3
EUROPEAN STANDARD

NORME EUROPÉENNE

October 2019
EUROPÄISCHE NORM
ICS 11.100.10
English Version

Molecular in-vitro diagnostic examinations - Specifications
for pre-examination processes for venous whole blood -
Part 3: Isolated circulating cell free DNA from plasma (ISO
20186-3:2019)
Analyses de diagnostic moléculaire in vitro - Molekularanalytische in-vitro-diagnostische Verfahren
Spécifications relatives aux processus préanalytiques - Spezifikationen für präanalytische Prozesse für
pour le sang total veineux - Partie 3: ADN libre venöse Vollblutproben - Teil 3: Aus Plasma isolierte
circulant extrait du plasma (ISO 20186-3:2019) zirkulierende zellfreie DNA (ISO 20186-3:2019)
This European Standard was approved by CEN on 14 September 2019.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 20186-3:2019 E
worldwide for CEN national Members.

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EN ISO 20186-3:2019 (E)
Contents Page
European foreword . 3

2

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SIST EN ISO 20186-3:2020
EN ISO 20186-3:2019 (E)
European foreword
This document (EN ISO 20186-3:2019) has been prepared by Technical Committee ISO/TC 212 "Clinical
laboratory testing and in vitro diagnostic test systems" in collaboration with Technical Committee
CEN/TC 140 “In vitro diagnostic medical devices” the secretariat of which is held by DIN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by April 2020, and conflicting national standards shall be
withdrawn at the latest by October 2022.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes CEN/TS 16835-3:2015.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 20186-3:2019 has been approved by CEN as EN ISO 20186-3:2019 without any
modification.

3

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SIST EN ISO 20186-3:2020
INTERNATIONAL ISO
STANDARD 20186-3
First edition
2019-09
Molecular in vitro diagnostic
examinations — Specifications for
pre-examination processes for venous
whole blood —
Part 3:
Isolated circulating cell free DNA
from plasma
Analyses de diagnostic moléculaire in vitro — Spécifications relatives
aux processus préanalytiques pour le sang total veineux —
Partie 3: ADN libre circulant extrait du plasma
Reference number
ISO 20186-3:2019(E)
©
ISO 2019

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ISO 20186-3:2019(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2019
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
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Fax: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2019 – All rights reserved

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ISO 20186-3:2019(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2  Normative references . 1
3  Terms and definitions . 1
4 General consideration . 5
5 Outside the laboratory . 5
5.1 Specimen collection . 5
5.1.1 Information about the specimen donor/patient . 5
5.1.2 Selection of the venous whole blood collection tube by the laboratory . 6
5.1.3 Venous whole blood collection from the donor/patient and stabilization
procedures . 6
5.1.4 Information about the specimen and storage requirements at the blood
collection facility . 7
5.2 Transport requirements . 7
6 Inside the laboratory . 8
6.1 Specimen reception . 8
6.2 Storage requirements for blood specimens . 8
6.3 Plasma preparation . 9
6.4 Storage requirements for plasma samples . 9
6.5 Isolation of the ccfDNA .10
6.5.1 General.10
6.5.2 Using blood collection tubes with stabilizers .10
6.5.3 Using blood collection tubes without stabilizers .11
6.6 Quantity and quality assessment of isolated ccfDNA .11
6.7 Storage of isolated ccfDNA .11
6.7.1 General.11
6.7.2 ccfDNA isolated with commercially available kits .12
6.7.3 ccfDNA isolated with the laboratory's own protocols .12
Annex A (informative) Impact of pre-examination process steps on circulating cell free DNA
profiles in venous whole blood plasma .13
Bibliography .16
© ISO 2019 – All rights reserved iii

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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.
A list of all parts in the ISO 20186 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.
iv © ISO 2019 – All rights reserved

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Introduction
Molecular in vitro diagnostics has enabled a significant progress in medicine. Further progress is
expected by new technologies analysing profiles of nucleic acids, proteins, and metabolites in human
tissues and body fluids. However, the profiles of these molecules can change drastically during the
pre-examination process, including the specimen collection, transport, storage and processing.
Consequently, this makes the outcome from diagnostics or research unreliable or even impossible
because the subsequent examination might not determine the real situation in the patient, but an
artificial profile generated during the pre-examination processes.
Circulating cell free DNA (ccfDNA) profiles can change significantly after blood collection (e.g. release
of genomic DNA from cells in blood, ccfDNA degradation and fragmentation and ccfDNA quantity
change). Therefore, special measures need to be taken to secure good quality specimens for ccfDNA
[23]
examination. Studies have been undertaken to determine the important influencing factors .
Standardization of the entire workflow from specimen collection to the ccfDNA examination is needed.
This document standardizes the steps of the pre-examination phase of circulating cell free DNA
prepared from plasma of venous whole blood.
In this document, the following verbal forms are used:
— “shall” indicates a requirement;
— “should” indicates a recommendation;
— “may” indicates a permission;
— “can” indicates a possibility or a capability.
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SIST EN ISO 20186-3:2020
INTERNATIONAL STANDARD ISO 20186-3:2019(E)
Molecular in vitro diagnostic examinations —
Specifications for pre-examination processes for venous
whole blood —
Part 3:
Isolated circulating cell free DNA from plasma
1 Scope
This document provides recommendations and requirements on the handling, storage, processing
and documentation of venous whole blood specimens intended for circulating cell free DNA (ccfDNA)
examination during the pre-examination phase before an analytical test is performed. This document
covers specimens collected in venous whole blood collection tubes.
This document is applicable to any molecular in vitro diagnostic examination performed by medical
laboratories. It is also intended to be used by laboratory customers, in vitro diagnostics developers and
manufacturers, biobanks, institutions and commercial organizations performing biomedical research,
and regulatory authorities.
Different dedicated measures are taken for stabilizing blood genomic DNA, which are not described in
this document. Blood genomic DNA is covered in ISO 20186-2.
Different dedicated measures are taken for preserving DNA in circulating exosomes, which are not
described in this document.
NOTE ccfDNA obtained from blood by the procedures cited in this document can contain DNA originally
[8][9]
present in exosomes .
DNA in pathogens present in blood is not covered by this document.
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 15189:2012, Medical laboratories — Requirements for quality and competence
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 http: //www .electropedia .org/
3.1
analyte
component represented in the name of a measurable quantity
[SOURCE: ISO 17511:2003, 3.2, modified — The example has been deleted.]
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3.2
backflow
flow of a liquid opposite to the usual or desired direction
3.3
blood collection set
intravenous device specialized for venipuncture consisting of a stainless steel beveled needle and tube
(tubing) with attached plastic wings and fitting connector
Note 1 to entry: The connector attaches to an additional blood collection device, e.g. a blood collection tube.
3.4
blood collection tube
tube used for blood collection, usually with a vacuum which forces blood from the vein through the
needle into the tube
3.5
ccfDNA
circulating cell free DNA
extracellular human DNA present in blood and plasma
[8][9]
Note 1 to entry: ccfDNA can include DNA present in vesicles such as exosomes .
3.6
ccfDNA profile
circulating cell free DNA profile
amount of different ccfDNA molecules, present in blood and plasma that can be measured in the absence
of any losses, inhibition and interference
3.7
closed system
non-modifiable system provided by the vendor including all necessary components for the pre-
examination and/or examination (i.e. hardware, software, procedures and reagents)
3.8
DNA
deoxyribonucleic acid
polymer of deoxyribonucleotides occurring in a double-stranded (dsDNA) or single-stranded
(ssDNA) form
[SOURCE: ISO 22174:2005, 3.1.2]
3.9
DNase
deoxyribonuclease
enzyme that catalyzes the degradation of DNA into smaller components
3.10
examination
analytical test
set of operations having the object of determining the value or characteristics of a property
Note 1 to entry: Processes that start with the isolated analyte and include all kinds of parameter testing or
chemical manipulation for quantitative or qualitative examination.
[SOURCE: ISO 15189:2012, 3.7, modified —"analytical test" has been added as additional preferred
term; Notes to entry have been deleted; new Note 1 to entry has been added.]
2 © ISO 2019 – All rights reserved

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3.11
examination performance
analytical test performance
analytical performance
ability of an examination procedure to measure or detect a particular analyte
Note 1 to entry: Analytical performance is determined from analytical performance studies used to assess the
ability of an in vitro diagnostic examination procedure to measure or detect a particular analyte.
Note 2 to entry: Analytical performance includes such characteristics as analytical sensitivity, detection limit,
analytical specificity (interference and cross-reactivity), trueness, precision and linearity.
[SOURCE: ISO/TS 17822-1:2014, 3.2, modified — Two preferred terms have been added.]
3.12
examination provider
analytical test provider
entity that provides the specific analytical test
3.13
needle holder
barrel used in routine venipuncture procedures to hold the blood collection tube in place and to protect
the phlebotomist from direct contact with blood
3.14
pre-examination processes
preanalytical phase
preanalytical workflow
processes that start, in chronological order, from the clinician's request and include the examination
request, preparation and identification of the patient, collection of the primary sample(s),
transportation to and within the medical laboratory, isolation of analytes, and end when the analytical
examination begins
Note 1 to entry: The pre-examination phase includes preparative processes, e.g. ccfDNA isolation procedures,
which influence the outcome of the intended examination.
[SOURCE: ISO 15189:2012, 3.15, modified — An additional term has been added and more detail have
been included in the definition; Note 1 to entry has been added.]
3.15
primary sample
specimen
discrete portion of a body fluid, breath, hair or tissue taken for examination, study or analysis of one or
more quantities or properties assumed to apply for the whole
[SOURCE: ISO 15189:2012, 3.16, modified — Notes to entry have been deleted.]
3.16
proficiency testing
evaluation of participant performance against pre-established criteria by means of inter-laboratory
comparisons
[SOURCE: ISO/IEC 17043:2010, 3.7, modified — Notes have been deleted.]
3.17
RNA
ribonucleic acid
polymer of ribonucleotides occurring in a double-stranded or single-stranded form
[SOURCE: ISO 22174:2005, 3.1.3]
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3.18
RNase
ribonuclease
enzyme that catalyzes the degradation of RNA into smaller components
3.19
room temperature
temperature in the range of 18 °C to 25 °C for the purposes of this document
Note 1 to entry: Local or national regulations can have different definitions.
3.20
sample
one or more parts taken from a primary sample
[SOURCE: ISO 15189:2012, 3.24, modified — The example has been deleted.]
3.21
stability
ability of a specimen or sample, when stored under specified conditions, to maintain a stated property
value within specified limits for a specified period of time
[SOURCE: ISO Guide 30:2015, 2.1.15, modified — The words “reference material” have been replaced by
“specimen or sample”.]
3.22
validation
confirmation, through the provision of objective evidence, that the requirements for a specific intended
use or application have been fulfilled
Note 1 to entry: The term “validated” is used to designate the corresponding status.
[SOURCE: ISO 9000:2015, 3.8.13, modified — Notes 1 and 3 to entry have been deleted, Note 2 to entry
has been renumbered as Note 1 to entry.]
3.23
venous whole blood
blood collected after directly puncturing a vein, usually with a needle and syringe, or other
collection device
3.24
verification
confirmation, through the provision of objective evidence, that specified requirements have been
fulfilled
Note 1 to entry: The term “verified” is used to designate the corresponding status.
Note 2 to entry: Confirmation can comprise activities such as
— performing alternative calculations;
— comparing a new design specification with a similar proven design specification;
— undertaking tests and demonstrations;
— reviewing documents prior to issue.
[SOURCE: ISO 9000:2015, 3.8.12, modified — Notes 1 and Note 2 to entry have been deleted; Note 3 to
entry has been renumbered as Note 1 to entry; new Note 2 to entry has been added.]
3.25
workflow
series of activities necessary to complete a task
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4 General consideration
For general statements on medical laboratory quality management systems and in particular on
specimen collection, reception and handling (including avoidance of cross contaminations) see
ISO 15189:2012, 4.2, 5.4.4, 5.4.6 or ISO/IEC 17020:2012, Clause 8 and 7.2. The requirements on
laboratory equipment, reagents, and consumables according to ISO 15189:2012, 5.3 shall be followed;
ISO 15189:2012, 5.5.1.2 and 5.5.1.3 and ISO/IEC 17020:2012, 6.2 can also apply.
All steps of a diagnostic workflow can influence the final examination result. Thus, the entire workflow,
including specimen/sample storage and transport conditions, and its impact on the stability of
biomolecules intended to be examined shall be verified and validated. Workflow steps which cannot
always be controlled shall be documented and their impact on the examination performance shall
be investigated and mitigation measures shall be established to allow the required examination
performance. In these cases, risk assessment is recommended.
CcfDNA profiles can change significantly after blood collection. The post-collection release of genomic
DNA from cells in blood can change the ccfDNA profile significantly (see A.1). Additional post-
[10][11][12][13]
collection effects can also occur, e.g. ccfDNA fragmentation . All these post-collection
changes can vary individually in specimens from different donors or patients, and they can also
[10][14][15][16]
depend on pathophysiological conditions . This can impact the validity and reliability of the
examination results (see A.2).
Before or during the design of an examination, it shall therefore be investigated and ensured that
the ccfDNA profile(s) intended to be analysed is/are not compromised in a manner impacting the
examination performance. This can be done, e.g. by applying the intended examination to specimens/
samples which underwent time course studies reflecting the individual pre-examination process steps
such as transport and storage and by implementing measures to prevent or reduce impacts by the
identified pre-analytical variables, e.g. by using blood collection tubes with stabilizers.
Safety procedures for handling and transport shall be in place. Safety requirements on transport and
handling shall be considered (see ISO 15189 and ISO 15190).
During the whole pre-examination process, precautions shall be taken to avoid cross contamination
between different samples/specimens, e.g. by using single-use material whenever feasible or
appropriate cleaning procedures between processing of different specimens/samples.
If a commercial product is not used in accordance with the manufacturer's instructions, responsibility
for its validation, verification, use and performance lies with the user.
5 Outside the laboratory
5.1 Specimen collection
5.1.1  Information about the specimen donor/patient
The documentation shall include the ID of the specimen donor/patient, which can be in the form of a code.
The documentation should include, but is not limited to:
a) the relevant health status of the specimen donor or patient [e.g. healthy, disease type, concomitant
disease, demographics (e.g. age and gender)];
NOTE In particular, e.g. cancer, inflammation, diabetes, hepatic disease, coronary disease, respiratory
[10]
syndrome, trauma, after exhaustive exercise , in elderly patients suffering from acute or chronic disease,
first trimester of pregnancy, placental disorders as pre-term labour, pre-eclampsia and malimplantation
[10][14][15][16]
have been reported to affect both ccfDNA quantity and fragmentation .
b) the information about medical treatment and special treatment prior to blood collection (e.g.
anaesthetics, medications, fasting status);
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SIST EN ISO 20186-3:2020
ISO 20186-3:2019(E)

c) the type and purpose of the proposed examination requested;
d) the appropriate consent from the specimen donor/patient.
See also ISO 15189:2012, 5.4.4.
5.1.2  Selection of the venous whole blood collection tube by the laboratory
The ccfDNA profile can be influenced by inadequate venous whole blood collection procedures and
...