The RELIEF study (Reflux assEssment and quality of life improvement with micronized Flavonoids in chronic venous insufficiency [CVI]) is a prospective, controlled, multicenter, international study performed in patients with or without venous reflux. This study was conducted between March 1997 and December 1998 in 23 countries worldwide with the participation of more than 10,000 patients suffering from CVI. The European countries, the subject of this report, were represented by the Czech and Slovak Republics, Hungary, Poland, Russia, and Spain. The principal aims of the study were: 1. To validate the first quality-of-life scale specific to chronic venous insufficiency (CMVIQ) in different languages and to assess the evolution of quality of life in patients suffering from CVI, with or without venous reflux, treated with micronized purified flavonoid fraction (MPFF*) (1,000 mg/day). 2. To collect international epidemiologic data on venous reflux assessed with pocket Doppler and photoplethysmography. 3. To assess the evolution of symptoms and signs with a specific emphasis on edema through validated Leg-O-Meter measurement (heaviness, pain, cramps, sensation of swelling, edema) in patients suffering from CVI and treated with MPFF, 1,000 mg/day, during 6 months. The first country-by-country statistical analysis and the European consolidated analysis are now available. The CIVIQ questionnaires adapted to each participating country have been validated with highly significant validity and reproducibility (p<0.0001). All dimensions have demonstrated a highly significant and evolving improvement during the study. The results show several interesting findings concerning the epidemiologic data and, of these, two were particularly interesting: - More than 50% of patients suffering from CVI (class 0 to 4 of the CEAP classification) were reflux-free, which means that they were suffering from functional CVI. Patient distribution between the different classes of the CEAP classification changed in a statistically significant manner after 6 months' treatment with MPFF; the number of patients in the more severe classes decreased to the benefit of the less severe classes. Symptoms such as pain, leg heaviness, sensation of swelling, and cramps were significantly improved (p=0.0001). This was associated with a significant decrease in edema, when present, measured by leg circumferences with the Leg-O-Meter (p=0.0001). In conclusion, the European results of the RELIEF study showed the perfect validity and reproducibility of CIVIQ questionnaire adaptations, and the positive progression of quality-of-life scores on MPFF treatment. This progression was paralleled by clinical improvement of patients reflected not only by assessment of CVI symptoms and signs but also by evolution of the CEAP classification.