About the Authors
The authors' individual competing interests are at http://www.plosmedicine.org/static/editorsInterests.action. PLOS is funded partly through manuscript publication charges, but the PLOS Medicine Editors are paid a fixed salary (their salaries are not linked to the number of papers published in the journal).
Wrote the first draft of the manuscript: DB. Contributed to the writing of the manuscript: LC RM LP AR PS MW DB. ICMJE criteria for authorship read and met: LC RM LP AR PS MW DB. Agree with manuscript results and conclusions: LC RM LP AR PS MW DB.