Prevalence of mild cognitive impairment: subtypes, and as based on Clinical Dementia Ratings and Mini-Mental State Examination scores.

aMCI = amnestic mild cognitive impairment; naMCI = non-amnestic mild cognitive impairment; CDR = Clinical Dementia Rating; MMSE = Mini-Mental State Examination; NA = not applicable. Values are percentage prevalence (95% confidence interval). The objective cognitive impairment criteria for these classifications was for aMCI: performance in the bottom 6.681% of the relevant study for the memory domain; naMCI: performance in the bottom 6.681% of the relevant study for at least one harmonized cognitive domain other than and excluding memory; CDR: a rating of 0.5; MMSE: a score of 24–27. Standardized prevalence estimates were directly standardized for age group and sex, with the standard population being the total sample of all studies included in the analysis; data were imputed for the missing age ranges within Invece.Ab, PATH and Sydney MAS.Prevalence of mild cognitive impairment: subtypes, and as based on Clinical Dementia Ratings and Mini-Mental State Examination scores.