Participants
Diagnostic criteria
Dementia: DSM, ICD
Dementia due to AD: NINCDS-ADRDA, NIA-AA
Vascular dementia: NINCDS-AIREN
DLB: consensus criteria 1996, 2005
FTD: consensus criteria ...
MCI: any definition acceptable which includes core elements of an objective cognitive impairment
and absence of dementia, e.g. Petersen, Petersen modified, Albert core criteria. Details of the
definition should be recorded, including any criteria used to identify cause (such as AD biomarkers,
vascular, diagnosis of PD). These may form the basis of inclusions or exclusions if MCI due to a
particular condition is the population of interest.
Additional considerations about participants:
For reviews about cognitive enhancement in cognitively healthy participants
 Age range. Is the intervention relevant to all age groups or is it intended specifically for
older adults?
 Special populations, e.g. shift workers.
 Recruitment method, e.g. volunteers.
 Methods used to exclude cognitive impairment.
For reviews about prevention of dementia
 Primary (cognitively healthy) or secondary (MCI) – can be in same review, but should be
treated separately
 Age range, e.g. mid-life and/or elderly
 Special populations, e.g. diabetic
 Recruitment method
 Methods used to exclude cognitive impairment or dementia
 MCI diagnostic criteria.
For reviews about treatment of MCI and/or dementia
 Diagnostic criteria, including subtypes
 Special populations, e.g. diabetic
 Recruitment method
 Setting, e.g. institutional care
Do not use 'Alzheimer's disease' as synonymous with 'dementia due to AD'
If intervention is potentially disease-modifying, e.g. for AD, then in most cases will be interested in
all stages of the disease, i.e. (preclinical AD), MCI due to AD, dementia due to AD.
MCI due to AD. Title should then be 'X for Alzheimer;s disease.'
For some interventions, appropriate to include all dementia and consider subtypes as potential
subgroups. Particularly true for non-pharm or non-disease-specific interventions which would be
applied in practice to heterogeneous populations.
For some interventions, may even be appropriate not to be too strict about dementia definition,
again for pragmatic reasons, e.g. a care or rehab intervention for patients with dementia in a general
hospital or nursing home. Consider accepting the sort of quick test which might be used in practice
to identify cognitively impaired patient in those settings.
Interventions in cognitively healthy subjects - outcomes
Is the question of interest about (a) cognitive enhancement or (b) prevention of cognitive decline
and dementia?
These questions should not be combined in the same review because they call for different kinds of
studies.
The former question is likely to be addressed by studies of young people, often with short follow-up
and possibly a crossover design, with outcomes limited to neuropsychological tests. In this case, no
difference between groups indicates lack of efficacy.
The latter question requires parallel group studies of middle-aged or elderly people, treated and
followed up over a longer period of time with a broader set of outcomes. In this case, no difference
between groups indicates efficacy of the treatment (assuming that decline does occur in the control
group; if not, no conclusion can be drawn).