Funding for this research was provided by:
National Research Foundation of Korea (NRF-2019S1A5A8032445)
Received: 29 January 2020
Accepted: 17 May 2020
First Online: 27 May 2020
Ethics approval and consent to participate
: This study used a deidentified secondary dataset. Thus, it was exempted from review by the Institutional Review Board (IRB) of Ewha Womans University (IRB No. 201908–0021-01).
: Not applicable.
: The author declares that he has no competing interests.