The Allen Cognitive Levels is a categorisation of the quality of information that arouses attention and guides what the person does and says, from a coma to normal adulthood and can be used to describe a person's global ability to function.
The hierarchy in the scale means that the person can do everything described in their score and the scores below but cannot do anything above their score. The sequence resembles child growth and development. The qualities of sensorimotor information were derived from an analysis of the patterns of activity performance of normal children and cognitively disabled adults.
The advantage of a hierarchy is applied by assuming that:
- Information that is too high takes too much energy, so it is ignored.
- Information that is too low takes less energy and is either relaxing or boring.
- Interesting information uses just the right amount of energy because the information matches the person's best cognitive ability to function.
The ACLs measure the reduction in global ability to function and the remaining abilities. The ACLs are compared to other scales related to cognitive ability to function and mental disorders. Knowing about scale construction and what numbers can and cannot do helps to determine what kinds of comparisons are valid.