Received: 12 December 2020
Accepted: 5 July 2021
First Online: 15 July 2021
: The study was approved by the Ethics Committee of Seoul National University Bundang Hospital. This study adhered to ethical principles regarding medical research involving human subjects in accordance with the Declaration of Helsinki. Furthermore, this study, which aspired to protect the lives, health, privacy, and dignity of the participants, was approved by the appropriate Medical Ethics Committee. The requirement for informed consent from individual participants was waived because the study did not manipulate the environment or subjects, and relevant data was obtained from a large-scale database.
: Not applicable.
: The authors declared no potential conflicts of interests with respect to the research, authorship, and/or publications of this article.