Population statistics
Prevalence data | Demand & exclusion
No demand
- The user is not required to perceive anything by sight
Low demand
The user is required to have sufficient ability to do things like
- Read a newspaper headline (≈ 72 pt text)
- Recognise a friend at arm's length away
Moderate demand
The user is required to have sufficient ability to do things like
- Read a large print book (≈ 16 pt text)
- Recognise a friend across the room
High demand
The user is required to have sufficient ability to do things like
- Read ordinary newsprint (≈ 9 pt text) without difficulty
- Recognise a friend across the road without difficulty
Demand levels assume that any desired vision aids will be used.
Graph showing the number of people who would be excluded due to various demand levels
Important Note
These statements refer to the level of vision ability that a product or service demands, in order to use it. For a particular demand level, the 1996/97 Disability Follow-up Survey is used to calculate the total number of people who do not have this level of ability, and will therefore be excluded. The GB adult population was 45.6 million at the time of the survey. Please see the Framework section for more detail.