Published Online: June 19, 2014. doi:10.1001/jamaoto.2014.979.
Study concept and design: All authors.
Acquisition, analysis, or interpretation of data: Jahanshahi, Pazira, Poorolajal.
Drafting of the manuscript: Jahanshahi, Pazira, Farahani, Karkhanei, Poorolajal.
Critical revision of the manuscript for important intellectual content: Jahanshahi, Pazira, Hashemian, Shokri, Poorolajal.
Statistical analysis: Poorolajal.
Obtained funding: Jahanshahi.
Administrative, technical, or material support: All authors.
Study supervision: Jahanshahi, Poorolajal.
Conflict of Interest Disclosures: None reported.
Funding/Support: This study was funded by the Vice Chancellor of Research and Technology, Hamadan University of Medical Sciences.
Role of the Sponsor: The funder 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 Information: This study was part of an MD thesis in ear-nose-throat surgery. We thank the Vice Chancellor of Research and Technology of Hamadan University of Medical Sciences for financial support of this work.
Additional Contributions: The Vice Chancellor of Education, Hamadan University of Medical Sciences, provided technical support.