Definition 2: <6 month vs. >=6 month
There was no significant difference in length of hospital stay (MD, -0.09; 95% Cl, -0.54 to 0.37; P=0.70), with high heterogeneity (I2=62%). The sensitivity analysis indicated that noteworthy heterogeneity existed in two studies by Conforti2009 and Duron2020. Furthermore, when we omitted them, the heterogeneity decreased from 62% to 0% with a statistically significant p-value (P=0.005). The heterogeneity may have resulted from the small sample size in both trials. The heterogeneity may have resulted from the small sample size in both trials.