Determination of the longitudinal sensitivity of the AVVQ-Brazil quality of life questionnaire to non-surgical treatment of chronic venous disease

Abstract

Background: Sensitivity determines the efficiency and quality of construction of an assessment measure, but studies of the subject are scarce in the literature. Objective: To evaluate the longitudinal sensitivity of the AVVQ-Brazil to clinical changes after treatment for chronic venous disease (CVD). Methods: A longitudinal intervention study, with 112 chronic venous patients receiving elective treatment, assessed with CEAP, VAPS, AVVQ-Brazil, and VEINES-QOL/Sym at pre-treatment (baseline) and post-treatment (4 weeks). Differences in the scores for the scales at different times were evaluated using Student’s t test for paired samples and Wilcoxon’s z, which were also used to asses individuals by CEAP grade and assessment time. Effect size, confidence intervals, and partial η2 were used to determine the sensitivity of changes in scale scores over time. Correlations between changes in the scores of the same scales and between different scales were measured using Pearson coefficients, Spearman coefficients, and Kendall’s tau-b coefficient. Results: The mean age of the patients was 59.51 years. The majority were female (82.1%), with standing for prolonged periods (49.1%), had completed secondary (22.3%) or higher (25%) education, and had CEAP C2 (28.6%) or C6 (32.1%) clinical severity. The following results were observed: mean scale scores reduced from baseline to post-treatment, except for the Extent of Varicosities domain of the AVVQ-Brazil and the VEINES-QOL/Sym scales; sensitivity was low for the AVVQ-Brazil and its domains and for the VAPS, and was from low to high for the other scales; there were improvements or maintenance of CEAP grade after treatment; and moderate to excellent correlations between changes in scale scores over time. Conclusions: The AVVQ-Brazil is sensitive to longitudinal clinical changes after treatment for CVD and is an important measure for assessment of QoL and of disease severity in Brazil.