The full name of hypothyroidism is hypothyroidism, and the main examination items are serum TSH (thyroid-stimulating hormone), serum T3 (triiodothyronine), T4 (tetraiodothyronine), thyroid peroxidase antibody (TPOAb), thyroglobulin antibody (TgAb) and so on. 1. Serum TSH: The measurement of serum TSH is of great significance to hypothyroidism, the normal value is 0.35~5.5μIU/ml, if there is hypothyroidism, the TSH will usually be elevated. 2. Serum T3 and T4: Serum T3 may be within the normal range in patients with mild hypothyroidism, and serum T3 value will be lower in severe cases. Most patients with hypothyroidism will have low serum T4. 3. TPOAb and TgAb: Thyroid antibodies are the main indicators for determining the cause of primary hypothyroidism and diagnosing autoimmune thyroiditis (including Hashimoto’s thyroiditis and atrophic thyroiditis). Patients with hypothyroidism may also need to undergo some other tests, and it is recommended that they follow the doctor’s instructions.