TABLE 3. Psychometric Characteristics of Functional Scales in a Study of the Relationship Between Cognitive and Performance-Based Measures.

Characteristic	Scale and Group
	UCSD Performance-Based Skills Assessment			Alzheimer's Disease Cooperative Study– Activities of Daily Living Inventory
	Cognitively Normal	Mild Cognitive Impairment	Alzheimer's Disease	Cognitively Normal	Mild Cognitive Impairment	Alzheimer's Disease
Skew	0.40	−0.29	−0.23	−3.52	0.16	−0.89
Kurtosis	1.85	−0.30	−0.80	14.09	−0.70	0.51
Coefficient of variation	11.86	14.85	40.72	6.24	5.42	16.57
Shapiro-Wilk normality test	0.97	0.98	0.96	0.55***	0.96	0.94

^***p<0.001.