Disability vs Handicap vs. Impaired

I like this reply to one of these postings.

I know a few people in wheelchairs - they all hate the term disabled because it implies one is unable to function. Handicap is the word they prefer as it implies they can function but not without a challenge. The word was changed by people who are NOT in wheelchairs, do-gooders that should butt out.

You can check out an article in BMJ here;

Impairment, disability and handicap—old fashioned concepts?

 207 pages of definition from the WHO here; I'm sure your doctor has it memorized.

International Classification of Impairments, Disabilities, and Handicaps

I prefer handicap