Estimated number of people with dementia in mainland China, Hong Kong and Taiwan (Based on DSM-IV).

a.Since most of their prevalence studies of dementia in Hong Kong and Taiwan recruited the participants aged 65 and over, it is more reasonable to estimate age-stratified prevalence from 65 years old and apply these estimates to the population aged 65 and over.b.The prevalence in mainland China considered the people aged 60 and above while in Hong Kong and Taiwan, the prevalence focused on the population aged 65 and over.