Ethics approval and consent to participate
MAY
The study was approved by the Ethics Committee of the Korea University Guro Hospital Institutional Review Board (approval number: 2019GR0178) on May 22, 2019, and written informed consent was obtained from all subjects and their legal guardian(s) prior to data collection or study intervention. All procedures were performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki and its later amendments.