Table 2.

Factor loadings of quality aspects items according to the exploratory factor analysis with oblimin rotation

nr	Item description	loading	α1	α2	ITC
	Factor 1: Communication with ophthalmologist		0.89
Q7	Ophthalmologist treated me with respect	0.88		0.88	0.66
Q8	Ophthalmologist listened carefully	0.90		0.87	0.73
Q9	Ophthalmologist explained things clearly	0.75		0.88	0.67
Q10	Ophthalmologist spent enough time	0.85		0.87	0.74
Q11	Ophthalmologist went seriously into merits of my questions	0.81		0.87	0.78
Q12	Ophthalmologist shared decision making	0.68		0.87	0.74
Q13	Ophthalmologist took specific wishes into account	0.68		0.87	0.74
Q16	Ophthalmologist talked about things that went wrong	0.40		0.91	0.49
	Factor 2: Communication with nurses		0.72
Q30	Nurses treat me with respect	0.84		0.66	0.56
Q31	Nurses listened carefully	0.84		0.59	0.63
Q32	Nurses explained things clearly	0.80		0.62	0.56
Q38	Information was adequately coordinated*	0.41		0.76	0.41
	Factor 3: Communication about medication		0.79
Q50	Questions asked about allergic iodine	0.91		0.69	0.65
Q51	Questions asked about allergic medication	0.92		0.58	0.74
Q52	Clear information about side-effects medication	0.61		0.83	0.51
	Factor 4: Rest items		0.52
Q16	Ophthalmologist talked about things that went wrong	0.41		0.43	0.33
Q38	Information was adequately coordinated	0.53		0.36	0.44
Q39	Care was adequately coordinated	0.57		0.36	0.40
Q63	How often did insurers compensate for costs medication	0.46		0.61	0.12

Note: Cronbach's alpha of the whole scale (α1), Cronbach's alpha of the scale if item was deleted (α2), and corrected item total correlation (ITC) for the domains are shown. Factor loadings exceeding 0.40 are displayed. Q14, Q15, and Q49 were unrelated to any of the four factors and were not displayed.

* low corrected item total correlation (ITC) and an increase of the Cronbach's alpha of factor 2 if Q38 was deleted (α = 0.76) led to the exclusion of Q38 from factor 2.