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Usability and accessibility: are they two sides of the same coin and does it matter anyway? Penny Garrod UKOLN University of Bath Bath, BA2 7AY Email [email protected] URL http://www.ukoln.ac.uk/ UKOLN is supported by: 1 Contents of session 1. Warm up exercise: (10 minutes) What do we mean by Accessibility? What do we mean by Usability? Do we need to differentiate? 2. Discussion: which guidelines?: RNIB/NLB; W3C; Government guidelines; Ch.14 of Resouce’s Manual of Best Practice (VIPs) etc. 3. Evaluation: Tools for testing: the Wave; Bobby; Lynx Viewer…. 4. Advice from other organisations and usability gurus:e.g. Microsoft; HE sector; Jakob Nielsen. 5. Conclusions and list of resources 2 Accessibility v. Usability Accessibility •Technical guidelines •Adapting a visual medium so that everyone can use it • accessible to wide range of disabilities e.g. dyslexia; colour blindness; sensory and physical impairment; not all disablities are visible •Also benefits non-disabled users e.g hands busy situations Usability “A measure of how easy is it for users to find their way around your website” (APLAWS desk top study) • can task be effectively carried out and information found? • User testing required • involve users from outset; design in stages – testevaluate-improve cycle Universal accessibility: serving largest possible audience using broadest range of systems; needs of users with disabilities considered 3 Guidelines and advice What have you used and found useful? RNIB A-AAA conformance What do OeE advise? “Be both acessible and usable” Enable citizens to find what they want and what they’re interested in. Legal imperative: DDA; EC resolution (E-Europe 2002 – adopt WAI guidelines at all levels of government) UK Government policy = Level ‘A’ WAI conformance (likely to be AA soon) OeE website guidelines –framework for local government; Illustrated Handbook for web management teams Best Practice manual 4 Guidelines and advice from OeE •Content: ask users to test it and find out if they can find, understand and use all your website offers •Advice from user research – use plain language; short, scannable text with subheads; bulleted lists •PDF documents – provide alternatives e.g. HTML and plain text • Branding – consistent look and feel throughout helps users; design features to give local, non-government feel • Avoid reproducing documents aimed at internal audience on public website •See section 2.4 of illustrated handbook: building in universal accessibility; + section 2.5 on browsers; long checklist provided •Special needs: technophobic; socially excluded; older people; non-english speakers • use W3C accessibility guidelines and quick tips; minimum ‘A’ (priority 1 items) rating required 5 Guidance from RNIB Blind people use IE + screen reader + keyboard (tab+enter keys) - not mouse Personalised settings – people’s needs change from day to day so not good idea to set these Plug-ins: need installing, seen as barrier to users; problem with silent pages (images only); Flash software not liked by RNIB (there are ‘accessibility kits’ available from Macromedia) Forms – these should work in linear style for screen readers Images – ‘alt-text’ tag is essential; functional description or “ ” null text for non functional images Do not recommend separate text only site 6 Other sources of advice from Resource’s Best Practice Manual ch. 14 •Stick to the official W3C web content accessibility guidelines •Use Lynx Viewer to see how page looks with text only and how it will be interpreted by screen reader •Use W3C HTML validator service to check code against version used •Use cascading style sheets to separate content from display structure Techdis: http://www.techdis.ac.uk/ (good resources aimed at HE but generally useful) APLAWS – http://www.aplaws.org.uk “a desktop study of usability issues for web site design” – lists key resources + useful info on CSS, frames, screen resolutions etc. Trace center (University of Wisconsin- Madison, USA) Designing more usable websites: http://www.trace.wisc.edu/world/web/index.html 7 Evaluation: Tools for testing the Wave – from Pennsylvania Institute on Disabilities (free) Bobby - from Watchfire (test one page free – pay for downloadable version to test entire site as batch c.$99) Lynx Viewer (free) Vischeck (from Stanford University) – simulates colour blindness and Daltonize which corrects images for colourblind viewers (both on Vischeck site) Questions How useful are these tools? How reliable are they? Do they take too much time and effort to use and interpret results? 8 Web-based tools: the WAVE Pennsylvania’s Initiative on Assistive Technology from: http://www.temple.edu/inst_disabilities/piat/wave Wave can’t tell you if page is accessible - no automated tool can adds icons and text to help you judge if page is accessible; provides information to help you exercise judgment downloadable tutorial Incorporates browser check e.g. – “I'm using a recent browser” (Internet Explorer 5, Navigator 6, Opera 4 or higher) – Analyze No-Frame Version Downloadable ‘Wave’ button (like Google) 9 10 Wave analysis of Hampshire’s entry point http://www.hants.gov.uk 11 http://bobby.watchfire.com/ 12 Bobby: Browser compatibility test http://bobby.watchfire.com/bobby/html/en/advanced.jsp 13 Lynx Viewer http://www.delorie.com/web/lynxview. html 14 Saga home page: www.saga.co.uk/ 15 Saga site viewed with Lynx Viewer 16 Vischeck: www.vischeck.com/ 17 Advice from other organisations and gurus Jakob Nielsen (2000) Designing Web usability:the practice of simplicity. Indianapolis,Ind.:New Riders. His web site: http://www.useit.com/ the book: useful tips e.g. content should account for 50% of page- preferably 80%; navigation <20%; use resolution independent design (use percentages of available space) as most people still use small monitors (800x600) suggests you identify top 3 reasons why people come to your site; simple things should be simple to do remember users are goal-driven Website very useful resource: re Flash usability; age related stuff; e-commerce usability etc. 18 Where else can I find advice? Microsoft: http://www.microsoft.com/enable/ Lists assistive technology for different categories of disability; tutorials for Microsoft users e.g. windows users with visual impairment; adjusting computers for mobility needs. Techdis: http://www.techdis.ac.uk/ designed for HE community but includes database of 2,500 items of assistive technology – applies to all learners How People with disabilities use the web (W3C) http://www.w3.org/WAI/EO/Drafts/PWD-Use-Web/Overview.html **APLAWS – A desktop study of usability issues for web site design: www.aplaws.org.uk - concise, clear, collation of much of what has been written to help local authorities avoid common mistakes; + lists of resources 19 W3C Ten quick tips for accessible websites 20 www.ukonline.gov.uk - normal view 21 Easy access version of UKonline 22 Conclusions? What do you think? 'image: www.freeimages.co.uk' 23