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The Case For the Use of Plain English to Increase Web Accessibility
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AbstractWithin the endeavour of work to increase the accessibility of web pages, little attention has been paid to the contribution that simplifying the textual content could make. Furthermore, attention needs to be given to alternative renderings of web page content as the web becomes more graphically and aurally orientated. This paper describes the role that Plain Language can play in supporting accessibility, particularly where textual content must be translated into sign language or speech, where Plain Language is clear and simple language which is both readable and understandable by the audience for which it is intended. It concludes that the use of plain language in web sites can aid accessibility for many categories of user including those with hearing or visual disabilities, or both as is the case with the deaf-blind population, but also for the population as a whole. 1. IntroductionAs part of a project with CACDP , the University of Durham is developing a strategy to help CACDP move all their products and services online, including an online Deaf Awareness course [1], Deaf Studies including British Sign Language (BSL) and a Directory of UK Interpreters. The Deaf Awareness Course will be designed to teach users about the subject of Deaf Awareness and examine their knowledge using a series of multiple-choice questions. In order to help determine the user requirements for the proposed systems, a survey was carried out of potential customers. Over 400 people, a response rate of over 20%, returned questionnaires about their use of computers and the web, their hearing status and their language preferences. One of the issues arising from the survey is that 20% of potential users of the site use BSL as their first or preferred language; for the remainder with negligible variations English is used. There are 8.7 million deaf or hard of hearing people in the UK, of which 50,000 use BSL as a first or preferred language [2]. This means that English is a second language for them, and they may therefore have difficulty understanding written English. The most common cause of hearing loss is ageing, so as the population of the UK is getting increasingly older, the proportion of people with hearing problems is growing [2]. Therefore, it is important to give consideration to the accessibility needs of deaf people. 2. How Can Sites be made more accessible for Deaf People?One of the most straightforward ways to make a site more
accessible to those with hearing impediments is to make the language content suitable
for many different levels of understanding, particularly BSL users for whom English
is a second language. For example, jargon and slang should be limited as this
can lead to confusion and misunderstanding as well as a less pleasant user experience
[ ]. Where specialised vocabulary, e.g. medical or legal terminology, cannot be
changed, there should be provision made for this in the design of the site, e.g.
by provision of a glossary giving explanations in simpler language. Some technical
jargon cannot be replaced with any other word or phrase, for example names of
processes or concepts, and it could be indicated somehow within the mark-up, for
example a <jargon> 3. How important is Accessibility?Tim Berners-Lee, W3C Director and inventor of the World Wide Web, stated, "The power of the Web is in its universality. Access by everyone regardless of disability is an essential aspect" [ ]. The accessibility of web sites is a very important and well-documented subject. There are many aspects of accessibility, from simple measures such as ensuring that all graphics have an alternative textual description available, to more complex issues such as testing the site with text-to-speech browsers, and providing access to multi-lingual versions of sites. US President Bill Clinton is also an advocate of the Web Accessibility Initiative, stating that: "Given the explosive growth in the use of the World Wide Web for publishing, electronic commerce, lifelong learning and the delivery of government services, it is vital that the Web be accessible to everyone" [ ]. The United States Government has recently extended their Federal IT Accessibility Initiative [ ] to include the legislation that all Federal web sites are accessible to those with disabilities. There is as yet no comparable legislation in the United Kingdom. A major difference between the needs of deaf people and those with other disabilities is that deaf people do not need specific technology to improve their access to the web. However, they do need designers and developers to consider accessibility when designing their sites, to make use of plain language, such as Plain English [26], to include ALT text for images (more for Deafblind people rather than Deaf people), and to provide text transcripts for audio and video clips. These are not changes that can be made by enabled-browsers, or other software solutions. Access for the visually impaired can be improved by the use of text-to-speech browsers and this is in the control of the user, rather than the designer or producer. Text-to-sign browsers are in development, but they are not yet good enough to provide signing-on-demand i.e. to load up any website in the world and have it translated by the browser. The major problems with Text-To-Sign browsers are that text does not translate word for word into sign language unlike speech. It would also require either a huge library of video clips, or a way of simulating the sign language using commands. Signing-on-demand is the ultimate ambition for these browsers as it would mean that users would be able to have any website translated for them without needing it to be specially designed. Other accessibility tools under the control of the user are those built into operating systems, for example, Microsoft Windows 2000 Accessibility Wizard. This allows deaf users to select an option that uses a visual indicator instead of a beeping sound to signal the arrival of new email, or to signal to the user when their input is in error. 4. Text-to-Speech browsers and Text-to-Sign browsersThere are many text-to-speech browsers already available, which are providing access to web pages for blind and visually impaired users. These are increasing accessibility but are being held back by the increase in the use of graphical interfaces as they deal most successfully with text-based interfaces. Screen readers that use speech cannot represent pictures adequately other than through a verbal description of the image [ ]. Work is being carried out on developing text-to-sign browsers for users of BSL. These are currently limited in their use. One of the major problems is that BSL and ASL do not translate word for word into English or vice-versa, as they have distinct grammars of their own, and therefore it would be difficult to translate a site directly. For example, the sentence "Please write down your address and phone number" would be indicated in BSL by pointing at the subject (you), then signing the object (address and phone number), then indicating the activity (write down) and finally "please". This is a very different way of "speaking". There are projects working on "Translation on Demand [ ]" but these are as yet limited in their application and success due to the problems with text-to-sign as outlined above. Ideally, as with text-to-sign, users would be able to speak into a microphone and have their words translated into sign and vice versa. There has been work on making use of remote human translators who receive the audio stream from a microphone, and then the video stream of their translation is relayed to the deaf person. The Visicast [ ] project proposes to develop the use of signing avatars on the web to provide signing-on-demand. The use of plain and simple language on the web will help to improve the performance of text-to-sign or text-to-speech browsers as the less complex language will be easier to translate. Currently some specialist software applications featuring sign language output exist. The project conducted a feasibility study [ ] of these systems in order to determine whether or not any of the approaches used for rendering sign language in these systems could be adapted for web based applications such as CACDP and the University of Durham plan to develop. While there is progress being made, the rendering that goes beyond the hand alphabet is all done by using hard-wired translations. 5. What is the current CACDP Situation?Currently, CACDP's web site and paper documentation are prepared by those with a specialist knowledge of plain language, but this is very subjective approach. There are no quantitative measurements to indicate whether it is a success or not. As a result of the survey, we have started looking into ways to make the proposed online system more accessible to deaf people as they make up a large minority of the potential CACDP site users. There are various tools and guidelines for making web sites more accessible to those users who are visually impaired, for example text-to-speech browsers such as JAWS [ ], or new mark-up languages such as VoiceXML [ ] or JSML [ ]. There are fewer that offer help on making sites accessible to those who are aurally impaired. Most of the current work on accessibility for the deaf focuses on inclusion of captions or text transcripts for audio and video, and ensuring that the audio or video is not crucial to the experience of the site. One issue that there is not much work on is the idea of making the language content of a site suitable for its intended users, e.g. through simplification. Although the CACDP recognise that this is a way in which sites can be made more accessible to those with hearing impediments, among others, they have not found much support from tools and guidelines when putting this into practice. The rest of this paper will focus on the use of Plain Language within web sites and how this can improve accessibility. 6. Readability IssuesOne issue when trying to improve the language content of a site, or when writing new text from the start, is how to measure the readability of the existing text. There have been many proposed methods of gauging readability of prose. These are generally based on formulae that use such variables as the number of sentences, and the average number of syllables in a word. For example, the Kincaid Formula is [ , ] The Flesch Easy Reading Formula, also known as the Flesch Index was developed by Flesch in 1948 and is based on school texts covering grades three to twelve. The index is between 0 (hard) and 100 (easy). Standard English documents usually rate 60 to 70 on this scale17. The formula for this index is [17, 18] The results of these formulae require specialist interpretation. There are simple ways to interpret the results, for example, if the document contains few words with many syllables then this will produce a higher score than if fewer words with few syllables are used. Both Kincaid and Flesch Formulae are based on American School Grades. The theory is that a user who reads up to a certain grade level will be able to understand 90%+ of the text. The Kincaid Formula was developed in order to judge the readability of technical manuals used by the American Navy. The result from the analysis is a school grade, ideally 7 or 8 (age 13/14), that indicates the level of education needed to understand the text [ ]. One of the problems with these readability indexes is that they do not indicate how readable text is for those whose first language is not English, or those who are used to a visual language. Nevertheless these indexes are relatively easy to apply to the text of a web site in order to get some comparative measures. These formulae were applied to two web pages, the current CACDP homepage [ ] and a prototype of the new Deaf Awareness System [ ]. The results are shown below. These have been obtained from two sources. webstyle is a simple UNIX/Linux shell pipeline program which analyses the text and produces a number of statistics and measurements based on specific readability formulae, as follows: lynx -dump $1|style|less where the -dump option to lynx dumps the first file to stdout and exits. This uses the lynx browser [ ] and the gnu version of style [ ] originally developed as part of the UNIX Writer's Workbench [ ] as suggested by Stutz [ ]. A full listing of the output from webstyle is given in Appendix A. The second set of statistics have been obtained from the grammar and spelling checker provided with Microsoft Word 2000. Statistics from Web-Style CACDP Page Deaf Awareness Course Kincaid 13.4 15.6 Flesch Index 44.9 30.3 Statistics from Word 2000 CACDP Page Deaf Awareness Course Flesch-Kincaid 12.0 12.0 Flesch Reading 34.4 31.4 Both programs were used to produce statistics as this shows the variation in results even when the same formulae are claimed to be used for calculation. Note the formulae used in Microsoft Word 2000 to calculate both statistics are the same as those used in the webstyle program. It is not clear why the two systems return differing results but it can be assumed that it is due to differences in implementation and interpretation of parameters such as sentence, word and syllable. For these measures to be useful to web developers, more work is required to give an interpretation of these results specifically relating it to the web page under development. It is doubtful that web developers will find these results of much value in their present form, other than as crude indicators of readability. 7. The Plain English CampaignOne starting point for English-speaking site developers to achieve this aim of clear and simple language is to ensure that a site conforms to the Plain English Standards as set out by the Plain English Campaign [ ]. The Plain English Campaign defines Plain English as "something that the intended audience can read, understand and act upon the first time they read it. Plain English takes into account design and layout as well as language" [ ]. The aim of the Plain English Campaign is to "fight for crystal-clear language and against jargon, gobbledygook and other confusing language" [27]. In order to be considered to be written in Plain English, a document or web site must avoid words and phrases which have double meanings, avoid the use of slang and jargon, and substitute simple words where the more complex are not necessary, for example utilise can be replaced with use. The Plain English Campaign offers an "Internet Crystal Mark" for web sites that conform to the high standards expected [ ]. This is an extension of their Crystal Mark Scheme for paper documents. The Internet Crystal Mark takes into account not only the text content but also the layout and navigation aspects of a site to ensure that readers can find the information they are looking for, clearly and easily. The Plain English Campaign award an annual "Plain English Web Award" to the clearest website of the year which was won by Yorkshire Dales National Park Authority [ ] in 2000. The Plain English Campaign produces a set of guidelines or tips for designing clear websites [ ]. These guidelines are mainly based around navigation and layout advice and do not offer any advice on simplifying language so that it conforms to the standards. One problem with the Plain English Campaign is that they require that documentation or web sites are submitted to their organisation in order to be checked. There is no automatic checking facility, such as Bobby [ ]. This is an online service offered from the Bobby web site which can check a web page (or whole site if the downloadable version is used) for various accessibility checkpoints, for example, that all images have an ALT tag, or that tables contain defined header cells. However, Bobby does not perform any checks on the text content of a site. 8. The Main Beneficiaries of Plain Language on Web SitesThere are many distinct groups of people who would noticeably benefit from the use of Plain English in web sites, as well as the general population as a whole. Users who have a first language that is not English would benefit from simpler vocabulary and shorter sentences. The removal or limitation of slang and jargon would aid comprehension generally and allow sites to be culturally acceptable. Those with learning difficulties or limited reading skills would also benefit from simpler vocabulary and less complex grammatical constructs, as would people with dyslexia. Deaf Users who prefer visual languages such as BSL or ASL may find reading less complex language easier, and those who are blind or visually impaired and choose to have web sites read to them through a Text-to-Speech browser would find shorter sentences easier to take in aurally. Approximately 1 in 10 of the population has some form of disability. Although not all disabilities affect a person's ability to access the web, there are many which can have an effect and these should be addressed. Plain language is a basic requirement for almost all web developments, as the following quote from the Bobby web site makes clear: "Using clear and simple language promotes effective communication. Access to written information can be difficult to impossible for people who have cognitive disabilities, learning disabilities, or who are deaf or hard of hearing. This consideration also applies to the many people whose first language differs from that of the web page. [ ]" 9. ConclusionsAccessibility is a very important consideration when designing or redesigning a web site. There are many groups of web users who would benefit from the use of Plain Language on web sites. It is easy to consider the language of a site and simplifying it can improve the site quality, particularly for translation either to sign language or any other language. This can be done by measuring the readability and then altering the site's textual content until the desired readability is achieved. Measures of readability give an indication of plain language but these need to be specifically refined to address the needs of translation of text to other languages, particularly suitability for translation into sign language. There are no established rules, only guidelines. Current determination of plain language is very subjective and there are few publicly available services online to check for plain language. One which attempts to measure readability is a tool provided by Clear Language and Design (CLAD) [ ]. Little work has yet been done on the improvement 10. References[ ] J Donkin, C Boldyreff, L
Burd and S Marshall, "Supporting Sign Language Users of Web-Based Applications:
A Feasibility Study", in Universal Access in HCI - Volume 3, edited by Constantine
Stephanidis, Lawrence Erlbaum Associates, 2001;
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