A profile of The Clinical Course of Cognition and Comorbidity in Mild Cognitive Impairment and Dementia Study (The 4C study): two complementary longitudinal, clinical cohorts in the Netherlands

Table 2 Contents of data collection in the 4C studies

	Baseline	12 months	24 months	36 months	Assessed by	Source
Informed consent	√				Research assistant	Participant and informant
Demographics	√	√	√	√	Research assistant	Participant and informant
MMSE [35]	√	√	√	√	Physician	Participant
CDR [34]	√	√	√	√	Physician	Participant and informant
Subjective cognitive functioning [17]	√	√	√	√	Physician	Informant
Neuropsychological assessment	√	√	√	√	Psychologist	Participant
Physical examination & structural medical review	√	√	√	√	Physician	Participant and informant
Medications (prescribed & taken)	√	√	√	√	Physician	Participant and informant
Hospitalization (if any)		√	√	√	Research assistant	Participant and informant
Syndromal diagnoses	√	√	√	√	Physician	Participant and informant
Comorbidities (CIRS-G) [18]	√	√	√	√	Physician	Participant and informant
Frailty (Fried criteria + Frailty Index) [19, 20]	√	√	√	√	Research assistant	Participant and informant
DAD (disability assessment) [21]	√	√	√	√	Research assistant	Informant
GDS-15 (depression, self-reported) [22]	√	√	√	√	Research assistant	Participant
NPI (neuropsychiatric symptoms) [23]	√	√	√	√	Research assistant	Informant
Euroqol 5D [24]	√	√	√	√	Research assistant	Informant
Care resource use	√	√	√	√	Research assistant	Informant
Refusal or withdrawal data	√	√	√	√	Research assistant	Participant and informant
Institutionalization (outcome & date)		√	√	√	Research assistant	Participant and informant
Death (outcome & date)		√	√	√	Research assistant	Informant

ISSN: 1471-2377