Validity and test retest reliability of the vascular quality of life Questionnaire-6: a short form of a disease-specific health-related quality of life instrument for patients with peripheral arterial disease

Table 4 Test retest on item level

	PA %	RP (CI 95%)	RC (CI 95%)	RV (CI 95%)
Item 1 Activity	59	0.03 (−0.04–0.12)	−0.04 (−0.14–0.06)	0.11 (0.04–0.17)
Item 2 Symptom	60	−0.05 (−0.12–0.01)	0.02 (−0.07–0.11)	0.02 (0.01–0.04)
Item 3 Activity	68	−0.03 (−0.11–0.06)	0.07 (−0.15–0.01)	0.13 (0.04–0.22)
Item 4 Emotional	55	−0.07 (−0.15–0.00)	−0.02 (−0.12–0.08)	0.09 (0.03–0.14)
Item 5 Social	64	0.01 (−0.07–0.06)	0.03 (−0.05–0.12)	0.03 (0.01–0.05)
Item 6 Pain	63	−0.04 (−0.12–0.04)	−0.02 (−0.11–0.08)	0.10 (0.03–0.17)

PA = Percentage agreement, 100% means no change in the answers
RP = Relative position, RC = Relative concentration, RP and RC range from −1 to 1 and a systematic change occur when CI does not cover zero
RV = Relative rank variance, the higher RV the larger individual variation and zero means total absence of individual variance

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