Accepted for Publication: May 7, 2015.
Published Online: July 20, 2015. doi:10.1001/jamaneurol.2015.1241.
Study concept and design: Harrison, Calabresi.
Acquisition, analysis, or interpretation of data: All authors.
Drafting of the manuscript: Harrison.
Critical revision of the manuscript for important intellectual content: All authors.
Statistical analysis: Harrison, Oh, Caffo.
Obtained funding: Harrison, van Zijl, Calabresi.
Administrative, technical, or material support: Harrison, Roy, Jones, van Zijl, Calabresi.
Study supervision: Izbudak, van Zijl, Calabresi.
Conflict of Interest Disclosures: Dr Harrison has received research support from Bayer Schering Pharma and EMD Serono and has received consulting fees from EMD Serono, Genzyme, Mallinckrodt Pharmaceuticals, and MedImmune. Dr Oh has received personal compensation for consulting or speaking from Biogen-Idec, EMD Serono, Genzyme, and Novartis. She also has received an unrestricted research grant from Genzyme. Drs Jones and van Zijl receive research support from Philips Medical Systems. Dr Calabresi has received research funding from Bayer, Biogen Idec, MedImmune, Novartis, and Vertex and honoraria for consulting from Abbott, Merck, Prothena, Vaccinex, and Vertex. No other disclosures were reported.
Funding/Support: This study was supported in part by National Institutes of Health supplemental grants 5P41 RR15241-09S1 and 5P41EB15909 (Dr van Zijl) and Bayer Neurosciences (Dr Calabresi). Time for data analysis was supported by National Institutes of Health–mentored grant K23NS072366 (Dr Harrison).
Role of the Funder/Sponsor: 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.
Additional Contributions: Janelle Aquino, BA, Michaela Seigo, BA, Stephanie Syc, BA, and Anna Whetstone, BA (Department of Neurology, School of Medicine, The Johns Hopkins University), helped with participant recruitment and study visit logistics; they received no financial compensation. We are also grateful to the dedicated Kirby Center staff, who make studies of this type possible.