Correction to: BMC Anesthesiology 20, 103 (2020)

https://doi.org/10.1186/s12871-020-01000-2

Following publication of the research article [1], we have been notified that some values were given incorrectly. In the section “Abstract-Results” stated that: the number of patients requiring analgesia postoperatively (WMD = 3.893, 95%CI: 2.053 to 5.733, P < 0.001), this values are incorrect and should be expressed as follows: WMD = 2.618, 95%CI: 2.040 to 3.361, P < 0.001. In the section “Results-Overall meta-analysis” stated that: the number of patients requiring analgesia postoperatively (WMD = 3.893, 95%CI: 2.053 to 5.733, P < 0.001), this values are incorrect and should be expressed as follows: WMD = 2.618, 95%CI: 2.040 to 3.361, P < 0.001. In the section “Results-VAS score at 24 h postoperatively” stated that: high-quality (WMD = 0.576, 95%CI: 13.594 to 39.558, P < 0.001), this values are incorrect and should be expressed as follows: WMD = 0.576, 95%CI: 0.048 to 1.104, P = 0.032.