A patient with a large saphenous varicose vein needs to be aware of the unsuitable people, contraindications before the test and the requirements of the test when performing the superficial venous valve function. 1. Unsuitable people: A patient with a large saphenous varicose vein should be aware of the inappropriateness of performing the superficial venous valve function test if there is a varicose vein ulcer. 2. Contraindications before the test: when performing the superficial venous valve function test, it is necessary to ensure normal dietary habits, sleep should be sufficient, and it is forbidden to stay up late or overwork. 3. Requirements: For superficial venous valve function test, it is necessary to tie a tourniquet or use finger pressure, but the pressure should be moderate, in order to block the reflux of the great saphenous vein. If a patient with varicose saphenous vein needs to have superficial venous valve function test, he should consult the doctor first. For patients with contraindications, they need to receive treatment first and then have superficial venous valve function test after their condition is stabilized.