Stand still for 5 minutes and observe the existence of any engorged vein, spider vein, or blue reticular vein (Figure 1)

Notice any edema of legs

Leg cramps especially at night

Leg soreness, swelling, heaviness, easy fatigue and restless leg.

Pigmentation or discoloration of calf (Figure 2) 

Unhealing calf wound or ulcer for a long time (Figure 3)

Personal or familial history of varicose veins

Occupational requirement for standing or sitting for a long time everyday

Constipation for a long time

Long-term use of female hormone or contraceptives