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NOTES ON THE DEMOGRAPHICS OF DISABILITY AND THE WWW

From: HumanITy <humanity@atlas.co.uk>
Date: Mon, 2 Apr 2001 11:17:24 +0100
Message-ID: <014f01c0bb5e$232633c0$98e136c3@oemcomputer>
To: "EOWG" <w3c-wai-eo@w3.org>
NOTES ON THE DEMOGRAPHICS OF DISABILITY AND THE WWW

KEVIN CAREY
Director
humanITy

2nd April 2001

  1.. Within the OECD, epidemiological and demographic data is not entirely comparable but differences are not statistically significant so that it is possible to make generalisations. In 'Intermediate' countries trends are rapidly following in the wake of the OECD. It is only in the poorest countries with high infant mortality rates and/or epidemics such as HIV/AIDS where the picture is more complex. These notes will not deal with this last group of countries, not because Web access by them is not important but because it would disproportionately extend these notes compared with the likely number of users over the next five years.
  2.. Within OECD and intermediate countries disability is largely a sub-set of ageing. There is a small, usually severe and chronic disability cluster which is a paediatric sub-set. It used to be argued in terms of uptake/days that multiplying the life span of the latter by the number of cases produced a higher figure of service use than making the same calculation for the former but the increase both in the number and life span of the elderly now invalidates that earlier assumption. In spite of the stereotypes used by fundraisers working for organisations for disabled people which focus on children, the typical disability case is not paediatric, traumatic and severe but is geriatric, onsets slowly and only becomes severe at a very late stage.
  3.. Just as any model of disability tends to show increased incidence and prevalence by percentage of the age group with any given syndrome at any given intensity, so there is an almost correspondent model which shows that the more severe the manifestation of any syndrome the fewer sufferers or, to put it another way, the milder the manifestation the more people have it.
  4.. Using a model which shows disability along a continuum where the majority are ageing tends to blur the traditional line between those who are disabled, classified according to epidemiology or entitlement to welfare, and those who are not classified and certainly would not classify themselves as disabled. One extremely confusing conflation for generalists is the tendency of disabled organisations to classify disability in its severe/traumatic/chronic/paediatric manifestation and then juxtapose this with statements such as "1 in 10 people are disabled". In the context of information and communications technology (ICT) this conflation presents service providers with such a daunting prospect that it hinders progress.
  5.. Epidemiological and welfare benefits classifications for disability are not co-terminal with functional disability in respect of ICT: a wheelchair user may have higher than average keyboard skills; a Nobel Prize winning chemist may not be able to navigate the Web effectively. There are also some additional complicating factors in reaching any final number for functional limitations in respect of ICT such as temporary loss of functionality as the result of accident or illness and the onset of mild, chronic conditions such as long or short sightedness and arthritis.
  6.. The disability model which seeks to separate disabled people form the rest of society has a number of serious disadvantages in the area of ICT:
  a.. First, as noted above, it leads to a general misunderstanding of the demographics
  b.. Secondly, it exaggerates the role of niche market specialist, add-on peripheral provision funded by the public sector and under-estimates the value of inclusive design in general systems
  c.. Thirdly, it sends the wrong signals about affordability. The age group with the highest disposable income is that where children have left home but where medical costs have not begun to become prohibitive, approximately 45-65; this is the same population group which are beginning to suffer mild disabilities most of which can be catered for in the ICT sector through good, inclusive design. Statistics also show the rising uptake and value of occupational pensions, insurance and annuities (in spite of recent debt/savings figures for the United States of America).
    7.   Functional limitation in ICT can be usefully grouped into four loose categories,
          shown here in descending order of magnitude:
  a.. Cognitive
  b.. Physical
  c.. Hearing
  d.. Visual.

        7.1    Cognitive. it is impossible to calculate the number of people who have 
                functional problems in the context of ICT as the result of cognitive difficulties 
                but a useful base figure is the OECD measurement of 'traditional' illiteracy at 
                between 14 and 21%, with the English speaking countries in the top band. As 
                each new skills requirement for effective ICT usage is added, the number of 
                those who cannot use the system effectively rises. Taking the traditional 
                illiteracy figure as a base, an estimate of 33% functional limitation with ICT 
                resulting from cognitive limitations is a conservative figure. 

        7.2    Physical. At first sight this figure should be lower than that for hearing limitations 
                but problems manipulating QWERTY keyboards and numeric keypads produce a 
                high figure, combining poor manual dexterity, hand/eye co-ordination, weak 
                grip/lack of manual flexibility (for operating a mouse). Many of these problems 
                will recede with the advent of more sophisticated voice-in/predictive applications.

        7.3    Hearing. As audio applications expand on the WEB, the ability to hear content 
                will increase. those who suffer from imperfect hearing averages at around 16% 
                of the population.

        7.4    Visual. The range of visual impairment is difficult to assess because of the 
                large number of people with visual impairments who are not classified or do not 
                self-classify as such. 6% would be a conservative figure.

    8.    As ICT develops it will affect different groups differently. As already noted, 
            improvements in voice-in/predictive will reduce the functional limitation of people 
            with physical difficulties and it will also assist people with certain kinds of cognitive 
            difficulties such as many people with dyslexia. The ubiquity of cell phones with tiny 
            displays will, on the other hand, pose additional problems with people with poor 
            vision.

    9.    Finally, a few other notes on demographics and the business case:

        9.1    If all the above are taken together (not added up because of the number who 
                have more than one mild disability) the range of those with accessibility problems 
                to digital information systems is 33-50%, many of whom either qualify for public 
                sector assistance with access or who have adequate income to meet their 
                individual needs.

        9.2    It might be helpful to consider the case for accessibility as layered with the 
                greatest degree of inclusiveness required of the public sector, followed by 
                monopoly and cartel private sector providers and then commercial organisations. 
                The degree of accessibility required of the civil society sector should be 
                variable, balancing cost against uptake to produce an optimal accessibility 
                criterion in each case. Indeed, the idea of what is optimal is at the base of the 
                inclusive design concept, attempting to draw a line between general systems 
                requirements and the requirements that can only reasonably be met by niche 
                market providers.

        9.3    It is important when looking at the demographics to recognise that the more 
                robust they are the better one is able to make recommendations about optimal, 
                inclusive design. it is also important to recognise what a business case is; it is a 
                calculation of what is optimal so that, for example, a Web site dealing with a topic 
                where the uptake by people with ICT limitations is likely to be tiny will, optimally, 
                have very few accessibility features if they cannot be engineered at near zero 
                cost into the basic design or procurement.
Received on Monday, 2 April 2001 06:17:00 GMT

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