Table 5. Optimal cut-off scores of K-IADL to diagnosis dementia and MCI, AUC, sensitivity, and specificity.

Variables		Optimal cut-off score	AUC	p-value	Sensitivity	Specificity	Positive predict value for dementia with 0.40	Positive predict value for dementia with 0.43*
In all participants							93.9%	92.5%
	Dementia vs. non-dementia	0.40	0.959	<0.001	0.901	0.916
	Dementia vs. MCI	0.40	0.952	<0.001	0.901	0.898
	MCI vs. normal	0.09	0.765	<0.001	0.736	0.776
In the patients with AD and MCI							94.2%	93.5%
	AD vs. MCI	0.40	0.964	<0.001	0.901	0.921
In the patients with VCI							100%	97%
	VaD vs. VaMCI	0.37	0.989	<0.001	0.962	0.956
In the patients with PD							84%	80%
	PDD vs. PD-MCI	0.35	0.944	<0.001	0.883	0.891

K-IADL: Korean-Instrumental Activities of Daily Living, MCI: mild cognitive impairment, AUC: area under the curve, AD: Alzheimer's disease, VCI: vascular cognitive impairment, VaD: vascular dementia, VaMCI: vascular MCI, PD: Parkinson's disease, PDD: Parkinson's disease dementia.

^*The cut-off score in the previous study.⁷