Fig. 4From: 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 diseaseThe contingency table (a) (T1 vertical = first measurement, T2 horizontal = second measurement) and the ROC curve (b) show no systematic disagree in concentration between the two assessments of item 3. ROC, relative operating characteristicBack to article page