Accepted for Publication: November 20, 2013.
Published Online: May 5, 2014. doi:10.1001/jamapediatrics.2013.5311.
Study concept and design: Tapiainen, Kujala, Renko, Kontiokari, Kristo, Alho, Uhari.
Acquisition, analysis, or interpretation of data: All authors.
Drafting of the manuscript: Tapiainen, Kujala, Koivunen, Kontiokari, Kristo, Pokka, Uhari.
Critical revision of the manuscript for important intellectual content: Tapiainen, Kujala, Renko, Koivunen, Kristo, Pokka, Alho, Uhari.
Statistical analysis: Tapiainen, Pokka, Uhari.
Obtained funding: Tapiainen, Uhari.
Administrative, technical, or material support: Renko, Uhari.
Study supervision: Koivunen, Kontiokari, Alho, Uhari.
Conflict of Interest Disclosures: None reported.
Funding/Support: This work was financially supported by the Pediatric Research Foundation, Finland, and Medical Research Foundation, Finland.
Role of the Sponsor: The funders 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.
Additional Contributions: Leevi Luotonen, MD, Department of Otolaryngology, Oulu University Hospital, was the main study physician from 1999 to 2001 and died in 2001.