ETR 095 TECHNICAL September 1993 REPORT

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ETR 095 TECHNICAL September 1993 REPORT ETSI ETR 095 TECHNICAL September 1993 REPORT Source: ETSI TC-HF Reference: DTR/HF-3001 ICS: 33.020, 33.040.40 Key words: Human factors Human Factors (HF); Guide for usability evaluations of telecommunications systems and services ETSI European Telecommunications Standards Institute ETSI Secretariat Postal address: F-06921 Sophia Antipolis CEDEX - FRANCE Office address: 650 Route des Lucioles - Sophia Antipolis - Valbonne - FRANCE X.400: c=fr, a=atlas, p=etsi, s=secretariat - Internet: [email protected] Tel.: +33 92 94 42 00 - Fax: +33 93 65 47 16 Copyright Notification: No part may be reproduced except as authorized by written permission. The copyright and the foregoing restriction extend to reproduction in all media. New presentation - see History box © European Telecommunications Standards Institute 1993. All rights reserved. Page 2 ETR 095: September 1993 Whilst every care has been taken in the preparation and publication of this document, errors in content, typographical or otherwise, may occur. If you have comments concerning its accuracy, please write to "ETSI Editing and Committee Support Dept." at the address shown on the title page. Page 3 ETR 095: September 1993 Contents Foreword .......................................................................................................................................................7 1 Scope ..................................................................................................................................................9 2 References..........................................................................................................................................9 3 Definitions and abbreviations ............................................................................................................10 3.1 Definitions ..........................................................................................................................10 3.2 Abbreviations .....................................................................................................................12 4 Background .......................................................................................................................................13 4.1 Introduction ........................................................................................................................13 4.2 Definitions of usability ........................................................................................................13 4.2.1 The ISO definition..........................................................................................13 4.2.2 The RACE definition......................................................................................13 4.2.3 The ETSI definition........................................................................................13 4.3 Types and approaches to evaluation .................................................................................15 4.4 Summary............................................................................................................................16 5 The usability evaluation process .......................................................................................................18 5.1 Introduction ........................................................................................................................18 5.2 The usability evaluation process........................................................................................18 5.2.1 Step 1: Definition of usability goals................................................................20 5.2.2 Step 2: Identification of the critical user, task and environmental characteristics ...............................................................................................20 5.2.3 Step 3: Specification of usability criteria........................................................20 5.2.4 Step 4: Prioritising the criteria .......................................................................21 5.2.5 Step 5: Usability specification tables .............................................................21 5.2.6 Step 6: Scenario building...............................................................................22 5.2.7 Step 7: Usability testing .................................................................................22 5.2.8 Step 8: Recommendations for improvements...............................................22 5.2.9 Verification and confirmation.........................................................................23 5.3 Measures, metrics and methods .......................................................................................23 5.3.1 Measures.......................................................................................................23 5.3.2 Metrics...........................................................................................................24 5.3.3 Methods.........................................................................................................24 5.2.4 Phases of development.................................................................................25 5.5 Supporting documentation.................................................................................................26 5.5.1 The test plan..................................................................................................26 5.5.2 The specification tables.................................................................................27 5.5.3 The test report...............................................................................................27 6 Describing the context.......................................................................................................................28 6.1 Introduction ........................................................................................................................28 6.2 The general procedure ......................................................................................................28 6.3 Identifying and describing users ........................................................................................28 6.4 Identifying and describing tasks.........................................................................................29 6.5 Identifying and describing the environment .......................................................................30 7 Evaluation methods...........................................................................................................................31 7.1 Introduction ........................................................................................................................31 7.2 Choosing a method............................................................................................................31 7.3 General description of the different methods.....................................................................32 7.4 The detailed description of the methods............................................................................33 7.4.1 Secondary sources........................................................................................33 7.4.1.1 Definition and components ..................................................33 7.4.1.2 Advantages and disadvantages...........................................34 Page 4 ETR 095: September 1993 7.4.1.3 Appropriateness for the development phases .................... 34 7.4.1.4 Application and analysis of results ...................................... 35 7.4.1.5 Conditions and precautions of use...................................... 35 7.4.1.6 Examples and illustrations .................................................. 35 7.4.2 Logging method ............................................................................................ 36 7.4.2.1 Definition and components ................................................. 36 7.4.2.2 Advantages and disadvantages.......................................... 36 7.4.2.3 Appropriateness for the development phases .................... 37 7.4.2.4 Application and analysis of results ...................................... 37 7.4.2.5 Conditions and precautions of use...................................... 37 7.4.2.6 Examples and illustrations .................................................. 37 7.4.3 Observation method ..................................................................................... 37 7.4.3.1 Definition and components ................................................. 37 7.4.3.2 Advantages and disadvantages.......................................... 38 7.4.3.3 Appropriateness for the development phases .................... 38 7.4.3.4 Application and analysis of results ...................................... 38 7.4.3.5 Conditions and precautions of use...................................... 39 7.4.3.6 Examples and illustrations .................................................. 39 7.4.4 Questionnaire method .................................................................................. 39 7.4.4.1 Definition and components ................................................. 39 7.4.4.2 Advantages and disadvantages.......................................... 39 7.4.4.3 Appropriateness for the development phases .................... 40 7.4.4.4 Application and analysis of results ...................................... 40 7.4.4.5 Conditions and precautions of use...................................... 40 7.4.4.6 Examples and illustrations .................................................
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