Meta-analysis was performed on the NfL levels of the GNO and the PNO groups at each time point of each study, and it was found that the NfL level in the PNO group was significantly higher than that in the GNO group (SMD = 0.553, 95% CI = 0.418–0.687 I2 = 65.5% P<0.05; Fig 2), and the ROC curve suggests that nfl has high specificity and sensitivity in predicting the prognosis of cardiac arrest patients(Fig 3). The gene discussed is NEFL; the disease is cardiac arrest.