Table 2.

Principal components analysis on the revised questionnaire (total variance explained); internal consistency of the Cambridge Behavioural Inventory revised, as measured by Cronbach's alpha.

Factor	Total eigenvalues	% of variance	Cumulative %	Cronbach alpha new groupings
1 = Memory and orientation and attention	6.7	14.8	14.8	0.93
2 = Challenging behaviour and disinhibition	5.1	11.2	26.1	0.87
3 = Everyday skills and self-care	4.3	9.5	35.5	0.89
4 = Motivation	3.9	8.7	44.2	0.91
5 = Mood	2.5	5.5	49.7	0.82
6 = Eating behaviour	2.5	5.5	55.2	0.76
7 = Abnormal beliefs	2.1	4.7	59.8	0.77
8 = Stereotypic and motor behaviours	1.8	3.9	63.8	0.69
9 = Sleep	1.67	3.8	67.5	0.58