Accepted for Publication: November 6, 2013.
Published Online: April 14, 2014. doi:10.1001/jamapediatrics.2013.5321.
Study concept and design: All authors.
Acquisition, analysis, or interpretation of data: All authors.
Drafting of the manuscript: Gidlöf, Nordenström.
Critical revision of the manuscript for important intellectual content: All authors.
Statistical analysis: Gidlöf, Nordenström.
Obtained funding: Wedell, Nordenström.
Administrative, technical, or material support: Wedell, Nordenström.
Study supervision: Wedell, Nordenström.
Conflict of Interest Disclosures: None reported.
Funding/Support: This study was supported by grant 12198 from the Swedish Research Council and by the Novo Nordisk Foundation, Karolinska Institutet, the Stockholm County Council, the Fredrik and Ingrid Thuring Foundation, Sällskapet Barnavård, Stiftelsen Frimurare Barnhuset, and the Centre for Gender Medicine at Karolinska Institutet.
Role of the Sponsors: The funding sources 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.