A series of tests are done for a bad thyroid to clarify what is wrong with the thyroid. For example, the presence of hyperthyroidism, hypothyroidism, or the presence of thyroid nodules. The main tests that need to be done are: 1. The testing of thyroid hormone levels requires a blood test at the hospital, which can reflect the patient’s thyroid function status. The results are used to determine whether the patient has hyperthyroidism, hypothyroidism, or normal thyroid function. 2. A more common test is the thyroid ultrasound, which is a simple and easy way to diagnose thyroid nodules. In addition to thyroid nodules, ultrasound examination of the thyroid gland is also useful in the diagnosis of hyperthyroidism or hypothyroidism.