Psychometric properties of the disease-specific health-related quality of life instrument VascuQoL in a Swedish setting

Table 3 Summary of results of multitrait/multi-item scaling tests of the Swedish VascuQoL questionaire

Multitrait/multi-item scaling tests
	Item-scale convergent validity		Item-scale discriminant validity		Scaling fulfillment
	Range of r	Criterion 1	Range of r	Criterion 2
Scale	Item-scale correlations ^a	% of item scale correlations ≥ 0.40 ^b	Correlation with other scales ^c	Number of items higher	Number of items that meet both criteria 1 and 2 ^e
Activity	0.25–0.71	88	0.04–0.70	7/8	7/8
Pain	0.51–0.66	100	0.38–0.66	2/4	2/4
Emotional	0.59–0.76	100	0.42–0.64	5/7	5/7
Social	0.55–0.55	100	0.48–0.70	0/2	0/2
Symptom	0.3–0.55	50	0.29–0.63	0/4	0/4

^aPearson correlations between items and hypothesized scale (corrected for overlap).
^bNumber of item-scale correlations that meet the minimum standard for convergent validity (r ≥ 0.40)/total numbers of correlations.
^cPearson correlations between items and competing scales.
^dCorrelations higher between items and hypothesized scale in comparison with all other scales.
^eItems in each scale that meet criteria for both item-scale convergent (Criterion1) and discriminant (Criterion 2) validity.

ISSN: 1477-7525