3.7 Adverse events
The incidence of adverse events was lower in the HIFU group than in the surgery group, with an overall RR of 0.32 (95% CI, 0.15 to 0.65, p=0.002, I2=35%) (Fig. 4). Among the included studies, the incidence of adverse events ranged from 0 to 15.38% in the HIFU group and from 0 to 47.06% in the surgery group. However, the inclusion criteria for patients varied across different studies, which might have affected the accuracy of the results.