Abstract:Abstract: Objective To study the combined detection of T3/FT3, T4/FT4, thyroid stimulating hormone (TSH), thyroglobulin antibody (TGAb), thyroid peroxidase antibody (TPOAb) for evaluating thyroid function in psychiatric disorders. Methods Serum T3/FT3, T4/FT4, TSH, TGAb and TPOAb levels were determined in 106 schizophrenia, 77 depression and 47 bipolar disorder patients and 77 healthy controls. The detection sensitivity and specificity of each parameter were assessed using receiver-operating characteristic (ROC) curve. Results FT4, TSH, TGAb, and TPOAb levels were higher in schizophrenia group than in control group (P<0.05). Compared with control group, T3 and TSH levels were lower, while FT4, TGAb and TPOAb levels were higher in depression group (P<0.01); T3 and T4 levels were lower, whereas TSH, TGAb and TPOAb levels were higher in bipolar disorder group (P<0.01 or 0.05). Combined detection of multiple parameters could significantly improve the diagnostic efficiency, with AUC≥0.87 of each parameter and the highest efficiency of combined seven indexes. Conclusion Combined detection of T3, FT3, T4, FT4, TSH, TGAb and TPOAb could be useful for assessing thyroid function in patients with psychiatric disorders.