About the Authors

Cynthia M. Boyd

cyboyd@jhmi.edu

Affiliation Division of Geriatric Medicine and Gerontology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland, United States of America

Daniela Vollenweider

Affiliation Division of General Internal Medicine, Department of Medicine, Johns Hopkins University, Baltimore, Maryland, United States of America

Milo A. Puhan

Affiliation Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Maryland, United States of America

Competing Interests

All authors have completed the Unified Competing Interest form at www.icmje.org/coi_disclosure.pdf (available on request from the corresponding author) and declare that (1) CMB and DPV had support from Robert Wood Johnson Foundation Physician Faculty Scholars Program for the submitted work and CB had support from the Paul Beeson Career Development Award Program (NIA K23 AG032910, AFAR, The John A. Hartford Foundation, The Atlantic Philanthropies, The Starr Foundation and an anonymous donor), and AHRQ R21 HS018597-01; (2) CMB, DV, and MAP have no relationships with companies that might have an interest in the submitted work in the previous 3 years; (3) their spouses, partners, or children have no financial relationships that may be relevant to the submitted work; and (4) CMB, MAP, and DPV have no non-financial interests that may be relevant to the submitted work. This does not alter the authors' adherence to all the PLoS ONE policies on sharing data and materials.

Author Contributions

Conceived and designed the experiments: CMB DV MAP. Performed the experiments: CMB DV MAP. Analyzed the data: CMB DV MAP. Wrote the paper: CMB DV MAP. Had the idea for the study: CMB MAP. Designed the study: CMB MAP. Developed the data collection form and collected the data: CMB DV MAP. Interpreted the data: DV MAP. Drafted the report: CMB. Revised the report for final publication: CMB DV MAP. Guarantors of this study CMB MAP. All authors had full access to all of the data (including statistical reports and tables) in the study and can take responsibility for the integrity of the data and the accuracy of the data analysis.