1、BSI Standards PublicationBS ISO 22077-1:2015Health informatics Medicalwaveform formatPart 1: Encoding rulesBS ISO 22077-1:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 22077-1:2015.It supersedes DD ISO/TS 11073-92001:2007 which is withdrawn.The UK partic
2、ipation in its preparation was entrusted to TechnicalCommittee IST/35, Health informatics.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for
3、 its correctapplication. The British Standards Institution 2015. Published by BSI StandardsLimited 2015ISBN 978 0 580 78918 2ICS 35.240.80Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and
4、 Strategy Committee on 30 April 2015.Amendments issued since publicationDate Text affectedBS ISO 22077-1:2015 ISO 2015Health informatics Medical waveform format Part 1: Encoding rulesInformatique de sant Format de la forme donde mdicale Partie 1: Rgles dencodageINTERNATIONAL STANDARDISO22077-1First
5、edition2015-04-01Reference numberISO 22077-1:2015(E)BS ISO 22077-1:2015ISO 22077-1:2015(E)ii ISO 2015 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2015All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any mea
6、ns, 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 ISOs member body in the country of the requester.ISO copyright officeCase postale 56 CH-1211 Geneva 2
7、0Tel. + 41 22 749 01 11Fax + 41 22 749 09 47E-mail copyrightiso.orgWeb www.iso.orgPublished in SwitzerlandBS ISO 22077-1:2015ISO 22077-1:2015(E)Foreword ivIntroduction v1 Scope . 12 Terms and definitions . 13 Abbreviated terms 14 Basic specifications 24.1 Basic attributes . 24.1.1 General 24.1.2 Sam
8、pling attributes . 24.1.3 Frame attributes . 34.2 Encoding rule . 44.2.1 General 44.2.2 Tag (T) . 44.2.3 Data length (L) . 54.2.4 Value (V) 64.3 Encoding principle . 64.3.1 General 64.3.2 Definition levels 64.3.3 General principles in interpretation, scope and priority of definitions . 65 Basic rule
9、s (Level 1) 85.1 Primary description 85.1.1 Sampling attributes . 85.1.2 Frame attributes . 95.1.3 Waveform 105.1.4 Channel . 135.2 Auxiliary rule . 145.2.1 Data description 145.2.2 Other definition .165.2.3 Information description . 176 Supplemental description (Level 2) 227 Extended description (L
10、evel 3) 24Annex A (informative) MFER conformance statement 27Annex B (informative) Description example .29Annex C (informative) Event information description .36Annex D (informative) Example of standard encoding.38 ISO 2015 All rights reserved iiiContents PageBS ISO 22077-1:2015ISO 22077-1:2015(E)Fo
11、rewordISO (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 tech
12、nical 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
13、 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
14、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 pa
15、tent 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
16、 constitute an endorsement.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT), see the following URL: Foreword Supplementary information .
17、The committee responsible for this document is ISO/TC 215, Health Informatics.iv ISO 2015 All rights reservedBS ISO 22077-1:2015ISO 22077-1:2015(E)IntroductionMedical waveform data such as an electrocardiogram (ECG) or an electroencephalogram (EEG) are widely utilized in physiological examinations,
18、physiological research, electronic medical records, healthcare information, and other areas in the clinical field. Medical waveform data can be used for many medical and research purposes if digital signal processing technology is applied to standardize the data in a digital format. For medical wave
19、forms, it is essential to standardize the data format to expedite the mutual application of the standard so that the data can be processed electronically and used in a variety of ways.Simple and easy implementation: application of medical waveform format encoding rules (MFER) is very simple and is d
20、esigned to facilitate understanding, easy installation, trouble-shooting, and low implementation cost.Harmonization with other standards: MFER is specially utilized to describe the medical waveform data. Other information than waveform data, such as patient demographic data and finding information,
21、etc. should be written using other healthcare standards, such as HL7, DICOM, ISO/IEEE 11073.In addition, experts in each field should independently develop relevant standards for medical specifications; for example MFER for ECG is developed by cardiologists and EEG is developed by neurologists.Combi
22、nation with coded information and text information: MFER policy is that both machine and human readable manner are used. Namely coded information is for computer processable and text data are for human readable information. Arterial blood pressure (ART) is coded as 129 and information description fi
23、elds indicate “Right radial artery pressure”, for example. As the description of MFER is quite flexible, MFER neither hinders the features of each system nor impedes the development of technologies. ISO 2015 All rights reserved vBS ISO 22077-1:2015BS ISO 22077-1:2015Health informatics Medical wavefo
24、rm format Part 1: Encoding rules1 ScopeThis International Standard specifies how medical waveforms, such as electrocardiogram, electroencephalogram, spirometry waveform, etc., are described for interoperability among healthcare information systems.This International Standard may be used with other r
25、elevant protocols, such as HL7, DICOM, ISO/IEEE 11073, and database management systems for each purpose.This is a general specification, so specifications for particular waveform types and for harmonization with DICOM, SCP-ECG, X73, etc. are not given.This International Standard does not include low
26、er layer protocols for message exchange. For example, a critical real-time application like a patient monitoring system is out of scope and this is an implementation issue.2 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.2.1framewaveform encoding un
27、it consisting of data blocks, channels, and sequences2.2medical waveformtime sequential data that are sampled by A/D converter or transmitted from medical equipment2.3samplingdata that are converted at a fixed time interval2.4channelindividual waveform data group3 Abbreviated termsAAMI Association f
28、or the Advancement of Medical InstrumentationA/D Analog to DigitalCSE Common Standards for Quantitative ElectrocardiographyCEN Comit Europen de Normalization/European Committee for StandardizationECG ElectrocardiogramINTERNATIONAL STANDARD ISO 22077-1:2015(E) ISO 2015 All rights reserved 1BS ISO 220
29、77-1:2015ISO 22077-1:2015(E)EEG ElectroencephalogramGPS Global Positioning SystemHL7 Health Level SevenDICOM Digital Imaging and Communications in MedicineIEEE Institute of Electrical and Electronic EngineersIEC International Electrotechnical CommissionJIS Japanese Industrial StandardLSB Least signi
30、ficant bitMFER Medical waveform Format Encoding RulesMSB Most significant bitOID Reference to the ISO standard.SCP-ECG Standard Communications Protocol for Computerized Electrocardiography (EN 1064)SPO2Saturation of Peripheral OxygenUID Reference to the ISO standardUUID Reference to the ISO standard
31、VCG Vectorcardiogram4 Basic specifications4.1 Basic attributes4.1.1 GeneralMedical waveform data described in accordance with the MFER consists of Sampling attributes (Figure 1), Frame attributes (Figure 2) and other supplemental information.4.1.2 Sampling attributesSampling information has two attr
32、ibutes, sampling rate and sampling resolution.a) sampling rateThe sampling rate is described with sampling interval or sampling frequency. The sampling interval stands for the time or distance interval of each sampled data as distributed sampled waveform data.b) sampling resolutionSampling resolutio
33、n represents a minimum sampling value per least significant bit (LSB).2 ISO 2015 All rights reservedBS ISO 22077-1:2015ISO 22077-1:2015(E)KeyT sampling interval (or frequency)R resolutionFigure 1 Sampling attributes4.1.3 Frame attributesThe frame is a waveform encoding unit consisting of data blocks
34、, channels, and sequences. A configuration example of a frame is shown as Figure 2.a) data blockThe data block is the waveform data array for each channel.b) channelsThe channels indicate different waveform groups, e.g. if three waveform groups exist, the number of channels is three.c) sequenceThe s
35、equence represents the repetition of the group with the data block and channel. ISO 2015 All rights reserved 3BS ISO 22077-1:2015ISO 22077-1:2015(E)Key1 frame2 data block3 channel4 sequenceFigure 2 Frame attributes4.2 Encoding rule4.2.1 GeneralThe header and waveform data should be encoded based on
36、the encoding rules which are composed of the tag, length and value (TLV), as shown in Figure 3.Tag (T)Data length (L)Value (V)Figure 3 Data unit The tag (T) consists of one or more octets and indicates the attribute of the data value. The data length (L) is the length of data values indicated in one
37、 or more octets. The value (V) are the contents which are indicated by tag (T); e.g. attribute definition, waveform data, etc.4.2.2 Tag (T)The tag is composed of a class, primitive/context (P/C) and tag number. The tag is classified into four classes (Table 1). Classes 0 to 2 are MFER standard codin
38、g and class 3 is for private use. The private definition is intended for special purposes but should be included within any updated future version.4 ISO 2015 All rights reservedBS ISO 22077-1:2015ISO 22077-1:2015(E)Table 1 Tag8 7 6 5 4 3 2 1Class P/C Tag number0 00/1MFER0 11 01 1 Privatea) primitive
39、 type (P/C = 0).P/C = 0 indicates a primitive description.b) context type (P/C = 1).This has only two tags which are group and channel definition on current MFER. Figure 4 gives an example of a group definition.87654321011 00111Figure 4 Group definition4.2.3 Data length (L)The data length indicates
40、the number of octets used for data values in the value (V) section (i.e. the length excluding octets used for tag and data length sections). The data length encoding method differs depending on whether the number of octets used for data are less than 127 or more than 128 octets.a) In case the data v
41、alue section uses 127 octets or less.The length is encoded in one octet, as shown in Figure 5.876543210Data lengthFigure 5 Data length 127 octetsb) In case the data value section uses 128 octets or more.The long data length can be encoded using multiple octets. The first octet indicates the number o
42、f octets used to represent the total data length. For example, two subsequent octets are used to indicate the waveform data length from 128 to 65 535 and thus three octets are used to encode the data length as in Figure 6. However, MFER allows representation of a data length using multiple octets ev
43、en if the length is less than 127 octets. For example, four octets can describe up to 4 294 967 295 bytes length as a data part.876543218765432187654321876543211Length number(e.g. 3octets)Most signig976icant octetThe second octetThe third octetFigure 6 Data length ISO 2015 All rights reserved 5BS IS
44、O 22077-1:2015ISO 22077-1:2015(E)c) Designation of indefinite data length.MFER allows designation of an indefinite data length by encoding 80 h on the top of the data length field (Figure 7). This indefinite length designation is terminated by encoding the end-of-contents (tag = 00, data length = 00
45、).TagP/C=1Length(80h)- - -End-of-Contents(00,00)Figure 7 Indefinite length designation and end-of-contents designationd) In case the data length is 0.MFER indicates that the definition indicated by tag resets to the default value. Namely, on the root definition the concerned items re-initialize to d
46、efault values and in case of the channel definition, the channel definition is re-initialized to the root definition.4.2.4 Value (V)The header or waveform data values are encoded in the value section according to descriptors specified by the tag.4.3 Encoding principle4.3.1 GeneralAll definitions in
47、MFER have default values, so any additional or amended definitions are optional. Thus the definition corresponding to each tag has a default value, so re-definition is not necessary if the default value is retained. It is expected that default definitions will suffice for most purposes.4.3.2 Definit
48、ion levels4.3.2.1 Level 1 basic definitionsDefinitions at level 1 are basic definitions, which are ordinary rules (marked with an asterisk) and ensure precise encoding.4.3.2.2 Level 2 supplementary definitionsDefinitions at level 2 are supplementary definitions. They may be used as required but it i
49、s desirable to associate the supplementary definitions with a host protocol where they can be defined with the host protocol.4.3.2.3 Level 3 extended definitionsDefinitions at level 3 are extended definitions, which should be used as little as possible. Items of these extended definitions may considerably affect the system with regard to security. Thus, great care should be taken in using them.4.3.3 General principles in interpretation, scope and priority of definitions4.3.3.1 Initial values (defa
