Author Contributions: Dr Drummond had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Study concept and design: Drummond, Dasenbrook, Pitz, Murphy, Fan.
Acquisition of data: Drummond, Dasenbrook, Pitz, Fan.
Analysis and interpretation of data: Drummond, Dasenbrook, Pitz, Murphy, Fan.
Drafting of the manuscript: Drummond, Dasenbrook, Pitz, Murphy, Fan.
Critical revision of the manuscript for important intellectual content: Drummond, Dasenbrook, Pitz, Murphy, Fan.
Statistical analysis: Drummond, Pitz, Murphy, Fan.
Administrative, technical, or material support: Drummond, Dasenbrook, Murphy, Fan.
Study supervision: Fan.
Financial Disclosures: None reported.
Funding/Support: Dr Drummond is supported by an Institute for Clinical and Translational Research (K12) Mentored Career Development Award from the National Institutes of Health. Dr Dasenbrook is supported by the Cystic Fibrosis Foundation (Clinical Fellowship Research Award DASENB07A0). Dr Pitz is supported by the University of Manitoba (R. Samuel McLaughlin/Manitoba Medical Service Foundation Research and Education Fellowship Award in Medicine). Dr Murphy is supported by an institutional training grant from the National Institutes of Health (T32 HL007534-26). Dr Fan is supported by the Canadian Institutes of Health Research (Fellowship Award) and the Royal College of Physicians and Surgeons of Canada (Detweiler Traveling Fellowship).
Role of the Sponsors: None of the funding organizations or sponsors had any role in the design and conduct of the study; the collection, management, analysis, or interpretation of the data; or the preparation, review, or approval of the manuscript.
Additional Contributions: We thank the following for their review of early drafts of the manuscript: Robert A. Wise, MD, Division of Pulmonary and Critical Care Medicine; Stephen D. Sisson, MD, and Christine Soong, MD, Division of General Internal Medicine; and Steven N. Goodman, MD, PhD, Department of Biostatistics, all at the Johns Hopkins University, Baltimore, Maryland; and Allan S. Detsky, MD, PhD, Department of Medicine, University of Toronto, Toronto, Ontario, Canada. None of these individuals received compensation for their review of the manuscript.