How is hypothyroidism diagnosed?

Since signs and symptoms of hypothyroidism are not specific, a health care professional diagnoses it with laboratory values. Most often, thyroid-stimulating hormone (TSH) levels are tested to determine if a patient has hypothyroidism. Also, free thyroxine (T4) levels are tested to determine if the patient has overt or subclinical hypothyroidism. Further testing is usually conducted to determine the cause of the hypothyroidism.^[1]