Statistical analysis

We assessed the effects of MNS on recovery from consciousness disorders in terms of five outcomes: GCS, ECG, DRS, cerebral blood flow, and days in the ICU. All outcomes were analyzed as continuous variables, and GCS scores were the primary outcome. We reported absolute differences between patients receiving different interventions and calculated pooled estimates of mean differences (MD) in all outcomes between MNS and control groups. The Cochrane I² test was used to assess heterogeneity among the studies.⁸ If heterogeneity was low (I² < 50%), we used the fixed-effects model for pooled analysis. If heterogeneity was high (I² values > 50%), we used a random-effects model to adequately account for the additional uncertainty associated with the use of data from different studies.

We categorized heterogeneity as low (I² values < 25%), moderate (I² values <50%), or high (I² values >50%). If heterogeneity was high, a sensitivity analysis was performed to explore the cause. The funnel plot and Egger test were used to assess small-study effects. Review Manager (RevMan 5.3) and Stata 14.0 were used for all statistical analyses. p < 0.05 was considered significant.