Developing a dementia-specific health state classification system for a new preference-based instrument AD-5D

Table 2 Summary statistics

		N (284)	% missing	Mean	Std. Dev.	Floor effect (% min score)	Ceiling effect (% max score)	Factor loading	Cronbach's alpha^a
Item 4	Living situation	256	9.86	1.754	0.839	8.59	17.19	0.341	0.843
Item 6	Family	259	8.80	1.931	0.828	7.72	23.17	0.683	0.852
Item 7	Staff	247	13.03	1.899	0.766	4.45	20.24	0.380	0.850
Item 8	Friends	237	16.55	1.814	0.797	7.17	16.88	0.590	0.844
Item 12	Live with others	239	15.85	1.703	0.820	8.79	14.23	0.465	0.840
Item 13	Make choices	229	19.37	1.729	0.820	9.17	14.41	0.398	0.837
Item 1	Physical health	276	2.82	1.634	0.849	12.32	11.96	0.814	0.846
Item 2	Energy	273	3.87	1.516	0.862	14.29	10.26	0.626	0.839
Item 9	Keep busy	243	14.44	1.593	0.864	13.17	11.93	0.757	0.839
Item 10	Do fun things	238	16.20	1.542	0.917	15.13	14.29	0.757	0.836
Item 11	Self-care	243	14.44	1.765	0.822	7.41	17.28	0.396	0.843
Item 3	Mood	261	8.10	1.586	0.793	9.96	9.20	-	0.842
Item 5	Memory	263	7.39	1.430	0.866	16.35	8.75	-	0.843

Abbreviations: Std. Dev. standard deviation, min minimum, max maximum
^aCronbach’s alpha for individual item is calculated as the overall alpha when the item is excluded from the pool

ISSN: 1477-7525