Much of the data on the numbers of people with impairments is derived from clinically based studies, which tend to use diagnostic measures rather than functional ones. These tend to produce figures showing the numbers in the population with hearing loss exceeding particular values, or the extent of specific conditions, such as multiple sclerosis. While such results are important for clinical management and resource allocation, they do not provide reliable information on the need for aids to mobility, hearing or vision. It is possible, with extreme care, to make some extrapolations from one data set to another, but usually only on the basis of some direct practical experience.
The user groups described in this brochure have been defined in terms of their functional ability, with specific emphasis on use of telephones, so that the needs of each might correlate with a particular set of equipment parameters. At the same time, it has been necessary to avoid straying too far from the more conventional descriptors, so that valid extrapolation of data can still be attempted. For example, 'Hearing impairment (moderate)' applies to a user group which employs hearing aids occasionally but does not need them when Telephoning, while 'Deaf' corresponds to a user group which cannot use voice Telephony and must resort to text or other visual modes. In attempting to estimate numbers in each user group, no account has been taken of multiple impairments.
In the elderly population in particular, there may be a tendency towards hearing, vision and mobility impairments arising in parallel. Therefore, while the numbers are 'best estimates' for single groups of users, they should not be aggregated. The group sizes have been estimated conservatively and very much larger numbers would be obtained if lower levels of impairment were included. For example, over half of the population needs some form of optical correction, and about one sixth has a clinically significant level of hearing loss. The lower levels of impairment will not normally lead to difficulties in using telephone terminals but can cause problems in adverse circum-stances.
The figures in this Website are based on the European Union which has a population of about 385 million.
For the purposes of this analysis links are provided to pages containing descriptions of the main characteristics of each of the 15 user groups identified.
|Estimated Numbers in the European Union|
|Hearing impairment (moderate)||16 million|
|Hearing impairment (severe)||4 million|
|Visual impairment (moderate)||3 million|
|Visual impairment (severe)||2 million|
|Speech impairment (moderate)||3 million|
|Speech impairment (severe)||2 million|
|Limited dexterity||7 million|
|Limited use of hands/arms||5 million|
|Weak grip||7 million|
|Hand tremor||7 million|
|Cognitive impairment||9 million|
|Restricted mobility (lower limb)||22 million|