GSTM1 and retinopathy of prematurity: According to the results of logistic regression analyses of hematologic parameters obtained at postnatal 4 weeks, risk of ROP development was negatively correlated with Hb (odds ratio [OR]=0.668, 95% confidence interval [CI]: 0.555-0.804, p<0.001) and platelet count (OR=0.997, 95% CI=0.994-0.999, p=0.036) and positively correlated with RDW (OR=1.282, 95% CI=1.012-1.624, p=0.040) and WBC count (OR=1.157, 95% CI=1.053-1.271, p=0.002).