Understanding the range of user capabilities

摘要

It is known that many products are not accessible to large sections of the population since designers instinctively focus on providing the necessary utility for someone with their physical and skill capabilities. They are either unaware of the needs of users with different capabilities, or do not know how to accommodate their needs into the design cycle. In the year 2002, 1000 million of the world population will have a noticeable degree of functional impairment (1). It is well established that impairments such as hearing, vision and reduced motor capability are of a degenerative nature and associated with increasing age. Legislation has forced organisations to consider designing products for impaired users. The declarative stipulations from the USA and the UK have been instrumental in encouraging an upsurge of initiatives in universal design (2) and design for all (3). However, better products will arise only if designers are able to evaluate them and characterise their target populations. To confirm the usability of a product or product concept, it is necessary to verify that the target users for the product are able to use it. This verification can take the form of users trials, expert assessment or a systematic analysis of the product interface. The latter option is attractive since it offers a low-cost, quick evaluation. Better still, it would be ideal if the designer understood the capabilities of the target population prior to designing the product. This paper will present the results of an analysis of data provided by the UK Department of Health and Social Security regarding the prevalence of disability in Great Britain (4, 5). This data was originally collected to assist Government in estimating the need for care. However, it may also be used to show the range of capabilities of the UK adult population, thus providing some insight into the characteristics of possible product target populations.