Table 1.

Demographic and clinical information collection in this multicenter study

Items	Subitems	Other information
Demographic data	Sex	Men or women
	Age at last visit	The age at patients’ last visit at each center
	Educational years
	Onset age	The onset ages were recorded according to patients’ and/or caregivers’ chief complaints. We conducted the onset ages of cognitive impairment (n = 1038) and parkinsonism (n = 781) in this study
	Interval between cognitive impairment and parkinsonism	The absolute value of onset age of cognitive impairment minus onset age of parkinsonism among the target patients. There were 781 pieces of data were analyzed, since a total of 781 patients (418 men and 363 women; 19 patients in MCI-LB, 331 patients in DLB, 118 patients in PD-MCI and 313 patients in PDD) had parkinsonism in this study
	Course of disease	Age at last visit minus onset age
Sex ratio		Sex ratios mean the number of men divided women (men/women)
Clinical core features	Fluctuating cognition	The presence was diagnosed with three or more “yes” responses required for structured questions from caregivers confirmed by the Mayo Fluctuations Composite Scale
	Visual hallucinations	The hallucinations item of 12-item NPI was used to determine the presence of hallucination, as complaining about by the patient and/or caregiver with specifically formed and detailed VH and illusions
	Parkinsonism	This is diagnosed by having one or more spontaneous cardinal features of parkinsonism included bradykinesia, rest tremor or rigidity evaluated by the motor section (Part III) of the Movement Disorders Society Unified Parkinson’s Disease Rating Scale (MDS-UPDRS)
	RBD	It can be confirmed by caregivers who mentioned five or more behaviors that are mentioned in the RBD screening questionnaire (RBD-SQ); or this patient was diagnosed by an overnight video polysomnography
Cognitive status	MCI or dementia
Clinical diagnosis at last visit	Probable MCI-LB, DLB, PD-MCI or PDD	The diagnostic criteria and clinical core features assessments are detailed described below
Neuropsychological assessments	Mini-Mental State Examination (Chinese version)	Scores range from 0 (severe impairment) to 30 (no impairment). It is used to evaluate global cognitive function
	Montreal Cognitive Assessment	Scores range from 0 (severe impairment) to 30 (no impairment), It is used to evaluate global cognitive function
	The Activities of daily living	Scores range from 20 (no impairment) to 80 (severe dysfunction), it is used to evaluate the functional status
	The Clinical Dementia Rating	Scores range from 0.5 (MCI), 1.0 (mild), 2.0 (moderate) to 3.0 (severe), it is used to evaluate the severity of dementia
	Neuropsychiatric Inventory*	Each subscale ranges between 0 (NPS) and 12 and the total composite score between 0 (no NPS) and 144, it is used to evaluate the presence and severity of NPS A total of 451 patients (61 patients with MCI-LB, 339 with DLB, 15 with PD-MCI and 36 with PDD) underwent NPI assessment in this study
MRI visual rating scales	Medial Temporal lobe Atrophy*	Scores range from 0 (no atrophy) to 4 (severe volume loss of hippocampal volume, it is used to evaluate the visual regional brain atrophy in the hippocampus, parahippocampal gyrus, entorhinal cortex and the surrounding cerebrospinal fluid spaces Multiplanar oblique coronal (perpendicular to the axis of the hippocampus), transverse and coronal position reconstructions were made of 3D T1-weighted images for diagnostic multisequence MRI. All of the MRI readings were reviewed by two experienced neuroradiologists double-blindly, and the final rating scores were averaged A total of 922 patients (74 patients with MCI-LB, 480 with DLB, 107 with PD-MCI and 261 with PDD) completed MRI visual rating scales
	Fazekas scales*	Scores range from 0 (no or single punctate lesion) to 3 (large confluent lesions), it is used to reflect the whole white matter lesion. The numbers of participants, the principles of MRI parameters and review are the same as described above
APOE genotype*		Genomic DNA was extracted from peripheral blood stored at -80 ℃, and the APOE gene was amplified by polymerase chain reaction. All genotypes were determined without knowledge of the patient status A total of 167 patients (40 patients with MCI-LB, 111 with DLB, 0 with PD-MCI and 16 with PDD) had the APOE genotype test

^*It means the items or subitems were optional to provide

RBD rapid eye movement sleep behavior disorder, MCI mild cognitive impairment, MCI-LB mild cognitive impairment with Lewy bodies, DLB dementia with Lewy bodies, PD-MCI Parkinson’s disease with mild cognitive impairment, PDD Parkinson’s disease dementia, NPS neuropsychiatric symptoms, MRI magnetic resonance imaging, APOE apolipoprotein E