According to 97% up limit of normal HVI in control group (5.0),the goiter rate at the ultrasonic level in 10-year-old children in this area (Minqing county)is 33. 6%.

• 以对照点儿童的身高甲状腺体积指数正常值的97%25上限值5.；0为标准，闽清县10岁儿童的甲状腺肿大率为33