IEC TR 63183:2019

IEC TR 63183 ®
Edition 1.0 2019-12
TECHNICAL
REPORT
colour
inside
Guidance on error and warning messages for software used in radiotherapy
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IEC TR 63183 ®
Edition 1.0 2019-12
TECHNICAL
REPORT
colour
inside
Guidance on error and warning messages for software used in radiotherapy

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 11.040.60 ISBN 978-2-8322-7715-7

– 2 – IEC TR 63183:2019 © IEC 2019
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 General guidance . 8
5 Designing error message displays . 8
5.1 Design systems to avoid the errors in the first place . 8
5.2 Categorize messages . 8
5.3 Consolidate reports and displayed error messages . 9
5.4 Summary of main concepts . 9
6 Message content usability guidelines . 10
6.1 Basic structure . 10
6.2 OPERATOR centred . 10
6.3 Message clarity . 10
6.4 Message action ability . 12
6.5 Conciseness . 12
6.6 Message specificity . 12
6.7 Courteous . 13
6.8 Use of error codes . 13
7 Guidelines for the development process . 13
8 Visual design guidelines . 14
(informative) Checklist . 15
(informative) Examples . 16
Bibliography . 23
Index of defined terms . 24

Figure 1 – Example error message answering what happened, why and what to fix . 10
Figure 2 – Example error message with unclear language on how to proceed . 11
Figure 3 – Example error message with unfamiliar OPERATOR abbreviations . 11
Figure 4 – Example error message implying the system thinks . 11
Figure 5 – Example of an unhelpful error message . 12
Figure 6 – Example error message showing error code . 13
Figure B.1 – Example 1. 16
Figure B.2 – Example 2. 16
Figure B.3 – Example 3. 17
Figure B.4 – Example 4. 17
Figure B.5 – Example 5. 17
Figure B.6 – Example 6. 18
Figure B.7 – Example 7. 18
Figure B.8 – Example 8. 18
Figure B.9 – Example 9. 19
Figure B.10 – Example 10 . 19

Figure B.11 – Example 11 . 20
Figure B.12 – Example 12 . 20
Figure B.13 – Example 13 . 20
Figure B.14 – Example 14 . 21
Figure B.15 – Example 15 . 21
Figure B.16 – Example 16 . 22
Figure B.17 – Example 17 . 22
Figure B.18 – Example 18 . 22

Table 1 – Replacing engineering language with language understandable for
operators . 10

– 4 – IEC TR 63183:2019 © IEC 2019
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
GUIDANCE ON ERROR AND WARNING MESSAGES
FOR SOFTWARE USED IN RADIOTHERAPY

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
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example "state of the art".
IEC TR 63183, which is a Technical Report, has been prepared by subcommittee 62C:
Equipment for radiotherapy, nuclear medicine and radiation dosimetry, of IEC technical
committee 62: Electrical equipment in medical practice.
The text of this Technical Report is based on the following documents:
Draft TR Report on voting
62C/738/DTR 62C/741/RVDTR
Full information on the voting for the approval of this Technical Report can be found in the
report on voting indicated in the above table.
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– 6 – IEC TR 63183:2019 © IEC 2019
INTRODUCTION
This document is intended to be read by persons involved in software development for
RADIOTHERAPY and provides guidance on how to write relevant error messages shown to the
clinical OPERATORS. This document is meant to provide examples within the RADIOTHERAPY
domain and is not meant to replace IEC/ISO standards governing usability (for example,
IEC 62366-1:2015). With the advent of more RADIOTHERAPY equipment being computer
controlled, there has been a reported increase in the number of treatment delivery errors, some
serious, occurring due to misunderstanding of the various error and warning messages shown
to the OPERATOR during usage. Mistakes in interpretation are more likely to occur when error
messages are written in technical language or are presented to the user without an OPERATOR-
friendly explanation.
This problem is compounded by use of the following practices:
– message dialogs are designed from the program’s technical point of view and not from the
clinical OPERATOR’S point of view;
– message dialogs are optimized for engineering purposes with little input from end USERS;
– insufficient attention and resources are given to applying good practices for usability of
message dialogs and careful review by clinical representatives.
In addition, the frequency of messages displayed by the many pieces of RADIOTHERAPY
equipment to the OPERATOR can lead to "message overload". This increases the RISK that the
OPERATOR will ignore critical information.
This document provides guidance via examples of common mistakes made when writing error
messages to be displayed to the OPERATOR.

GUIDANCE ON ERROR AND WARNING MESSAGES
FOR SOFTWARE USED IN RADIOTHERAPY

1 Scope
This document, which is a Technical Report, provides guidance on the usage and form of error
or warning messages written for software used in RADIOTHERAPY. It does not replace any
requirements existing in the safety standards but is meant to be used as a supplement to
existing standards on usability by providing specific examples in the field of RADIOTHERAPY.
The two main goals of this document are
1) to present in a concise manner the best practices and design guidelines for good message
dialogs, and
2) to illustrate these design guidelines with specific examples from the field of radiation
oncology.
This document is intended to be read by the following MANUFACTURERS’ employees and
representatives:
– engineering department members including: software engineers, RISK managers, quality
assurance engineers, technical writers, etc.;
– usability and human factors engineers;
– marketing representatives (product marketing, product managers, business analysts).
Throughout this document, unless specifically called out, these guidelines apply to all
categories of messages summarily called error or warning messages (e.g. critical error, warning,
system status, informational, routine interlock messages).
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.
IEC 60601-1:2005, Medical electrical equipment – Part 1: General requirements for basic safety
and essential performance
IEC 60601-1:2005/AMD1:2012
IEC 60601-2-1:—, Medical electrical equipment – Part 2-1: Particular requirements for the basic
safety and essential performance of electron accelerators in the range 1 MeV to 50 MeV
IEC TR 60788:2004, Medical electrical equipment – Glossary of defined terms
IEC 62366-1:2015, Medical devices – Part 1: Application of usability engineering to medical
devices
___________
Fourth edition under preparation. Stage at the time of publication: IEC/AFDIS 60601-2-1:2019.

– 8 – IEC TR 63183:2019 © IEC 2019
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60601-1:2005 and
IEC 60601-1:2005/AMD1:2012, IEC TR 60788:2004 and IEC 60601-2-1:— apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
4 General guidance
This document is meant to provide guidance to MANUFACTURERS of RA
...