- Correspondence to Dr Sung-il Cho, Department of Public Health Science, Graduate School of Public Health, Seoul National University, Seoul 08826, Korea;
- Received January 15, 2019
- Revised April 4, 2019
- Accepted May 1, 2019
- First published June 4, 2019.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.