1. Classification systems for describing mild cognitive impairment according to Matthews 2008.

System	Description	Impairment
Age‐related cognitive change
ACMI	Age‐consistent memory impairment	Memories aging in accord with normative expectations; individual aged 50 to 79 and reports a decline in memory verified using objective memory testing performance (within ± 1 standard deviation of aged norms on 75% of tests (memory) administered); preserved general functioning.
ARCD	Age‐related cognitive decline	Objectively identified decline in memory and cognitive functioning considered to be a normal consequence of aging.
Category systems
SMC	Subjective memory complaint	Self‐reported decline in memory.
MMSE MCI	Mini‐Mental State Examination	Classification based on MMSE cut‐offs (maximum score 30). 'Normal' defined as a score from 27 to 30; MCI defined as a score from 22 to 26; and 'impaired' defined as a score < 21.
Pathological decline
MNCD	Mild neurocognitive disorder	Impairment resulting from a general medical condition; reported decline in cognitive functioning supported by formal testing; deficits observed in at least 2 areas of cognitive functioning; interference in social, occupational, or other areas of functioning.
CIND	Cognitive impairment no dementia	Cognitive impairment in one or more domains (including memory and non‐memory domains) that can have a variety of aetiologies.
BSF	Benign senescent Forgetfulness	Impairment in remote memory and intact recent memory; awareness of the impairment and use of compensatory strategies.
AAMI	Age‐associated memory impairment	Subjective and objective memory loss associated with normal aging; individual aged 50 and older and shows adequate intellectual function (i.e. without dementia).
MD	Minimal dementia	Cognitive impairment in memory and minor and variable errors in orientation; no evidence of impaired occupational or social functioning; self care unimpaired.
LCD	Limited cognitive disturbance	Reported decline in memory with use of compensatory strategies; occasional forgetfulness (e.g. names, places); 1 or 2 errors on cognitive (memory) testing.
QD	Questionable dementia	Impaired memory and non‐memory test performance; no significant activity of daily living or instrumental activity of daily living interference.
AACD	Age‐associated cognitive decline	Self‐ or informant report of cognitive decline (gradual and present for 6 months); objective difficulties in any of the following domains: learning and memory, attention and concentration, thinking, language, and visuospatial functioning
MCD	Mild cognitive disorder	Decline in cognitive performance, including memory impairment and learning or concentration difficulties; complaint confirmed by cognitive tests; may precede, accompany, or follow a wide variety of infections or physical disorders.
Mayo Clinic Criteria
N‐MCI	Non‐amnestic mild cognitive impairment	Subjective memory complaint; normal general cognitive function; normal range of activities of daily living; objective impairment in 1 or more domains other than memory.
A‐MCI	Amnestic mild cognitive impairment	Subjective memory complaint; normal general cognitive function; normal range of activities of daily living; impaired memory performance; normal non‐memory test performance
M‐MCI	Multiple mild cognitive impairment	Subjective memory complaint; normal general cognitive function; normal range of activities of daily living; impaired memory and nonmemory test performance