GSTM1 and noise induced hearing loss: And no significant correlation between GSTM1 and NIHL was found in Mixed population (OR 0.776 95% CI 0.509–1.184) (NIHL cases: 508; control cases: 601) and Asian subgroup (OR 0.706; 95% CI 0.428–1.165) (NIHL cases: 377; control cases: 385), and no publication bias was observed (t = 0.41; p = 0.707) (Supplementary Figure S2A).