BRMS1 and medullary thyroid gland carcinoma: The heterogeneity test revealed absence of heterogeneity in expression of BRMS1 protein in different LNM status, TNM stages, tumor size, histological grades, pathological types, therefore leading to adoption of a fixed-effect model (LNM: P = 0.229, I 2 = 27.5%; TNM stage: P = 0.892, I2 = 0.00%; tumor size: P = 0.348, I2 = 10.2%; histological grade: P = 0.998, I2 = 0.00%; ductal carcinoma: P = 0.466, I2 = 0.00%; lobular carcinoma: P = 0.473, I2 = 0.00%; medullary carcinoma: P = 0.653, I2 = 0.00%) simulating heterogeneity.