Submitted for Publication: March 10, 2014; final revision received August 18, 2014; accepted August 30, 2014.
Published Online: November 20, 2014. doi:10.1001/jamaoto.2014.2926.
Study concept and design: B. G. Kim, Choi.
Acquisition, analysis, or interpretation of data: B. G. Kim, J. W. Kim, Park, S. H. Kim, H. N. Kim, Choi.
Drafting of the manuscript: B. G. Kim, Choi.
Critical revision of the manuscript for important intellectual content: J. W. Kim, Park, S. H. Kim, H. N. Kim, Choi.
Statistical analysis: B. G. Kim.
Obtained funding: B. G. Kim.
Administrative, technical, or material support: B. G. Kim, S. H. Kim, H. N. Kim, Choi.
Study supervision: Choi.
Conflict of Interest Disclosures: None reported.
Funding/Support: This research was supported by grant 2013M3A9D5072551 from the Bio and Medical Technology Development Program of the National Research Foundation of Korea (NRF), funded by the Ministry of Science, Information and Communication Technologies (ICT) and Future Planning; grant HI08C2149 from the Korea Healthcare Technology Research and Development Project, Ministry for Health and Welfare Affairs, Republic of Korea (J.Y.C.); and grant 2013R1A1A1061080 from the Basic Science Research Program through the NRF, funded by the Ministry of Science, ICT and Future Planning (B.G.K.).
Role of the Sponsor: The funding institutions had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.