Psychometric properties of the short version of the Freiburg Life Quality Assessment for chronic venous disease

Background: Chronic venous disease is a frequent vascular condition. International societies have recommended the use of health-related quality of life (HRQoL) instruments in the assessment of patients with vascular diseases. Thus, the Freiburg Life Quality Assessment for chronic venous disease, 10-item questionnaire (FLQA-VS-10) was developed. The aim of the present study was to validate the FLQA-VS-10 in a prospective study. Methods: We recruited 100 patients with recurrent varicosis or incomplete or complete venous insufficiency undergoing interventional vein treatment (high ligation of the great or small saphenous vein or endovenous ablation therapy). These patients completed the FLQA-VS-10 and instruments assessing convergent validation criteria at four points: preoperatively (T1), postoperatively (T2) and twice 3 years later with a 1-week interval (T3 and T4). Results: The mean age was 56.0 +/- 13.7 years, and 66.0% were women. The patients had presented with recurrent varicosis of the saphenofemoral junction (28.0%), recurrent varicosis of the saphenopopliteal junction (1.0%), incomplete or complete insufficiency of the great saphenous vein (69.0%), or complete insufficiency of the small saphenous vein (2.0%). The items showed few missing values. The FLQA-VS-10 global score showed no ceiling effect (patients reporting the highest possible impairments in H RQoL) but did show a floor effect (patients reporting the lowest possible impairments in HRQoL), which was highest at the postoperative assessments. The internal consistency of the global score was high at all measurement points. A convergent validity and responsiveness analysis revealed that the FLQA-VS-10 correlated in the expected direction with the convergent instruments, including the Freiburg Life Quality Assessment for venous diseases (venous disease-specific H RQoL) and the five-level EQ-5D (generic H RQoL). Data from T3 and T4 revealed high test-retest reliability (intraclass correlation, 0.92). Overall, the patients stated that the FLQA-VS-10 was comprehensible, comprehensive, and easy to complete. Conclusions: Our data suggest that the FLQA-VS-10 is a reliable, valid, responsive, and feasible HRQoL questionnaire for patients with chronic venous diseases. This questionnaire can serve as short and easy-to-use instrument to assess patient-reported outcomes in the treatment of these patients.