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Accessibility: The Current Situation and New Directions

Accessibility and Usability

Before embarking on the major strands of my argument it would be as well to consider definitions.

There is now a fine old Pharisaic, or perhaps we might better say Scholastic, discussion about the delineation of accessibility - the capability of a system to cater for the needs of disabled people - as a highly specific segment in the usability - the capability of a system to behave in a way which most closely accords with human behaviour - sector as a whole. This is best imagined as an accessibility core versus a usability outer section, with accessibility accounting for the most severe functional gap between person and system but the division defies the tactics of conventional turf wars. whereas execrable taxonomy, for example, the most salient and frequent shortcoming of web sites, is usually classified as a usability issue, the inability to use keyboard input, as opposed to the use of the mouse, is classically an accessibility issue; but good accessibility through the use of the keyboard, can overcome bad taxonomy. What we have learned, most notably in the framework for the outstanding DRC research on web accessibility [1], is that the key issue for those experiencing problems with digital information systems is the unified concept of task completion whose use of time and success rate can be measured, as opposed to much more abstract measurements of accessibility and usability. Only those who seek grants to split hairs will quarrel with the fundamental premise that what matters is the system's fitness for purpose which allows, for example, box offices to issue tickets, shops to sell goods and information systems to inform. On this basis, then, one should properly refer to task completion in the context of a functional gap between digital information systems and people but, having recognised this, I will use the traditional language of "Accessibility" as it refers in a shorthand way to the problems that disabled people experience with information systems but this shorthand will embrace some characteristics which are often described in terms of "Usability".

For brevity, let us assume that the core of people who experience accessibility problems as the primary barrier in their use of digital information systems are classifiable as "Disabled". Admittedly, this term is usually epidemiologically or administratively defined whereas many disabled people would prefer it to be self referential; but for the purposes of this Paper, I will assume the hybrid schedule of definitions in the Disability Discrimination Act (1995) [2], as amended by the DDA (2005) [3]. Whatever definitions are used, I believe that the following propositions are beyond dispute:

• Disability is almost entirely an adventitious phenomenon (in spite of the emphasis on paediatric disability in charity fund raising) whose incidence rises proportionately with age
• In almost all cases, as disabilities become more mild their incidence rises
• The four 'clusters' of disabling syndromes rank in descending order of incidence as follows:
  • Learning/cognitive/developmental
  • Physical/motor
  • Deafness/hearing impairment
  • Blindness/visual impairment
• Policy making and strategies for tackling paediatric disability challenges are radically different from those for adventitious disability
• The functionality gap between disabled people and information systems widens by cluster as follows:
  • Deafness/Hearing impairment
  • Physical/motor
  • Learning/Cognitive/Developmental
  • Blind/visually impaired. [4] [5] [6]

These figures are related to PC-based systems largely presenting text and static graphics; one would expect the ranking to alter, with problems for deaf and hearing impaired people increased, with the growth of multi media products without sub-titling.

Accessibility Methodology

As already noted, it is dangerous to define accessibility, as opposed to usability, features in the enabling of task completion but the following is a summary, most of which is embraced by the idea dealt with later of creating data multi modally; the exception is in the area of enabling simplification which is primarily required for those with learning, cognitive and developmental difficulties. The terms in brackets show where the original technique was developed but all of these will move in time across channels:

• Audio/Video Description (broadcasting): primarily used by blind and visually impaired people but useful for data access through devices without a screen or where the screen is not in the line of sight; this is a highly specialised skill which involves selecting and ranking material from the visual data which must be included in the audio file in speech gaps in the audio visual product. The material is mostly created but in some cases it simply involves providing audio information being shown on screen.
• Print Modification (publishing): primarily used by  visually impaired people but also useful for those with learning, cognitive and developmental difficulties, this involves the enablement of customisation of print size and font but it should also include the ability to moderate foreground and background colours and display intensity. This is often referred to as a "Large print" function but some visually impaired people require very small print. It is also important to allow an unjustified right margin and the turning off of proportionate spacing.
• Signing (broadcasting): exclusively for deaf and hearing impaired people, this subject is somewhat controversial as there is no call for this service in North America and its use in Europe is limited. It involves producing sign language on screen simultaneously with the finished broadcast; this can now be produced automatically with an avatar.
• Simplification (publishing): primarily required by those with learning, cognitive and developmental difficulties but also useful for those who find the written text difficult, this involves using integrated tools to simplify lexicography and/or summarise a document; nb the two processes may produce opposite effects as conventional shortening often involves jargon
• Speech synthesis (publishing): primarily used by blind and visually impaired people but also useful to those unfamiliar or unskilled with the written language being displayed, this involves translating the text file into synthetic speech.
• Sub-titling (broadcasting): Primarily for those who are deaf or hearing impaired but useful for those unfamiliar with the language delivered on the audio track. Many deaf people want the full text plus sound effects which may amount to 180 words per minute

Digital Information Systems

The second major issue of definition is my use of the term digital information system. This generic description is necessarily much wider than the usual concern with internet and web access. Public policy in the area of social inclusion or the "Digital divide" has erroneously concentrated on PC-based, as opposed to telephone and television-based, user interface experiences out of historical snobbery but the necessary analogue boundaries between the three channels will disappear and so it is much more helpful to think of digital information systems generically. One of the conclusions which will naturally emerge from this discussion, incidentally, is that internet publishers have much to learn from broadcasters about the culture of accessibility whereas broadcasters have much to learn from internet publishers about plasticity and interactivity.

The Functional Gap

Finally, on the subject of definition, I have already used the term "Functional gap" to describe the inadequate transactional outcome between digital information systems and people. I use this term most deliberately because the public policy analysis of why people have problems with digital information systems, notably those dependent upon the PC, has been predominantly anthropocentric. If only, politicians say, we could get alienated people to master word processing, the world would be a better place.

Regardless of whether or not this is true, the much more crucial issue is why these people have problems with PC/Windows bundles when they have no problems using VCR equipment, navigating the Sky Electronic Programme Guide, manipulating mobile phone settings, using SMS or, in a different field, passing a driving test, understanding the soccer off-side rule and finding items in supermarkets.

We should see this functionality gap as arising because of two major factors, the lack of skills or incentive on the part of the human user on the one hand and the deficiency in the design of the system and its user interface on the other. There is, to cite an apparently trivial example, something perverse about a system which requires the activation of the "on" switch to turn it off. Computer users with an incentive to master a system, easily forget its perversity until it either spontaneously modifies itself or an accidental operation is performed where in either case the correction is not susceptible to rational investigation. In a fundamental sense, almost universally overlooked by analysts and lobbyists who have an obsession with skills development, training in the use of systems is a cost shift from the producer to the consumer; the better the design, the more intuitive the functionality, the lower the degree of skill and training which are required to close the gap between system and user.

Fundamental Issues

In considering the functionality gap between disabled people and digital information systems, I will deal with three fundamental issues:

• First, the design of digital information;
• Secondly, the design of the user interface; and
• Thirdly, the impact on these of the convergence of  digital publishing and broadcasting.

Having considered these general issues I will make some specific remarks on accessibility in the context of the formal learning process.