Submitted for Publication: May 14, 2013; final revision received July 30, 3013; accepted August 2, 2013.
Published Online: January 2, 2014. doi:10.1001/jamaophthalmol.2013.6669.
Study concept and design: Lindblad, Wolk.
Acquisition of data: Lindblad, Wolk.
Analysis and interpretation of data: All authors.
Drafting of the manuscript: Lindblad.
Critical revision of the manuscript for important intellectual content: Håkansson, Wolk.
Statistical analysis: Håkansson.
Obtained funding: Lindblad, Wolk.
Administrative, technical, or material support: Wolk.
Conflict of Interest Disclosures: None reported.
Funding/Support: This study was supported by grants from the Swedish Council for Working Life and Social Research, Stockholm, Sweden, and the Örebro County Council, Örebro, Sweden.
Role of the Sponsor: The funding sources had no role in the design and conduct of the study; collection, management, analysis, or interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.