Definitions of the WHO’s International Classification of Impairments, Disabilities and Handicaps
| WHO 1980. | |
| Impairment | Any loss or abnormality of psychological, physiological or anatomical structure or function |
| Disability | Any restriction or lack of activity resulting from an impairment to perform an activity in the manner or in the range considered normal for people of the same age, sex, and culture |
| Handicap | A disadvantage for a given individual resulting from impairment or disability that limits or prevents the fulfilment of a role that would otherwise be normal for that individual |