Accepted for Publication: April 18, 2012.
Published Online: September 17, 2012. doi:10.1001/archneurol.2012.1481
Author Contributions: Drs P. J. Dyck and Ms Davies had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. Study concept and design: P. J. Dyck, Low, Litchy, P. J. B. Dyck, Bolton, England, Mauermann, Russell, and Tesfaye. Acquisition of data: Overland, Litchy, Andersen, Albers, England, Klein, Llewelyn, Mauermann, Selvarajah, Singer, Smith, and Vella. Analysis and interpretation of data: Low, Davies, Carter, Melton, Andersen, Albers, England, Selvarajah, Singer, Smith, Tesfaye, and Vella. Drafting of the manuscript: Low, Carter, Russell, and Selvarajah. Critical revision of the manuscript for important intellectual content: P. J. Dyck, Overland, Low, Litchy, Davies, P. J. B. Dyck, Carter, Melton, Albers, Bolton, England, Klein, Llewelyn, Mauermann, Russell, Selvarajah, Singer, Smith, Tesfaye, and Vella. Statistical analysis: Davies, Carter, and Selvarajah. Administrative, technical, and material support: Overland, Litchy, Albers, Klein, Russell, Singer, Smith, and Vella. Study supervision: Low, Andersen, and Vella.
Conflict of Interest Disclosures: None reported.
Funding/Support: This study was supported in part by the Kawamura Fund, by the Society for the Support of Neurologic Education and Research of Rochester, by grant NS36797 from the National Institutes of Neurological Disorders and Stroke, by grant AG034676-47 from the Rochester Epidemiology Project (principle investigator, Walter A. Rocca, MD), and by Mayo Foundation funds.
Additional Contributions: We received help from personnel in the Peripheral Neuropathy Research Laboratory, Electromyographic Laboratory, Quantitative Sensation Testing Laboratory, Autonomic Laboratory, and Section of Engineering at Mayo Clinic. Mary Lou Hunziker assisted with preparation of the manuscript.