Accepted for Publication: May 12, 2011.
Author Contributions: Both authors contributed equally to the creation of this manuscript; the order of authorship is entirely arbitrary. Both authors had full access to all of 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: Schwartz and Woloshin. Analysis and interpretation of data: Schwartz and Woloshin. Drafting of the manuscript: Schwartz and Woloshin. Critical revision of the manuscript for important intellectual content: Schwartz and Woloshin. Statistical analysis: Schwartz and Woloshin. Obtained funding: Schwartz and Woloshin.
Financial Disclosure: None reported.
Funding/Support: This study was supported by a grant from the Attorney General Consumer and Prescriber Education grant program and the Robert Wood Johnson's Pioneer Program.
Role of the Sponsors: Neither of the sponsors had any role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; and preparation, review, or approval of the manuscript.
Disclaimer: The views expressed herein do not necessarily represent the views of the Department of Veterans Affairs or the United States Government.
Additional Contributions: Alastair J. J. Wood, MBChB, from the Department of Pharmacology, Vanderbilt University, encouraged us to test directive explanations; Sir Iain Chalmers, DSc, from The James Lind Library, provided very thoughtful comments on an earlier draft of the paper; and Alice Andrews, PhD, from Dartmouth Institute for Health Policy and Clinical Practice, provided technical assistance. None of these individuals received any compensation.