Dementia is being badly diagnosed, a large worldwide study has recently discovered.
These findings could have serious implications for research and treatment, as well as for the right of many older people to drive and handle financial affairs, says the report, from the University of Helsinki, Finland and the University of Western Ontario, Canada.
The study, conducted in Europe and Canada, shows that there are many different sets of criteria used for diagnosing dementia. Even the most common criteria used can differ by as much as a factor of 10 in people classified with this disease.
In the survey of nearly 2000 people, the proportion of people with dementia ranged from 3.1 to 29.1 per cent, depending on the criteria used. Doctors barely managed to agree at all. When all the six different criteria were used, only 20 people were diagnosed with dementia (N Engl J Med,1997; 337:1667-74).