Table 4.

Principal component tests for polytomous variables by domain and overall.

Domain	Cronbach's alpha	Interclass correlation	Interval (95%CI)	KMO	Bartlett
Usefulness (D1)	0.785	0.785	0.739–0.826	0.819	<0.001
Acceptance (D2)	0.878	0.878	0.851–0.901	0.884	<0.001
Appropriateness (D3)	0.883	0.883	0.857–0.905	0.871	<0.001
Overall	0.945	0.945	0.934–0.955	0.952	<0.001