To the Editor:
The authors regret that there were errors in Affiliations.
Content of correction:
Yoon Jung Kim,1,2 Hee-Pyoung Park,1 Hee Seung Kim,3 and Sanghon Park4
1Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.
2Department of Anesthesiology and Pain Medicine, Inha University College of Medicine, Incheon, Korea
3Department of Obstetrics and Gynecology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.
4Department of Anesthesiology and Pain Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.