About the Authors

Jun Ma

Affiliation Stanford Prevention Research Center, Stanford University School of Medicine, Stanford, California, United States of America

Niraj L Sehgal

Affiliation Stanford Prevention Research Center, Stanford University School of Medicine, Stanford, California, United States of America

John Z Ayanian

Affiliation Division of General Medicine, Brigham and Women's Hospital and Department of Health Care Policy, Harvard Medical School, Boston, Massachusetts, United States of America

Randall S Stafford

To whom correspondence should be addressed. E-mail: rstafford@stanford.edu

Affiliation Stanford Prevention Research Center, Stanford University School of Medicine, Stanford, California, United States of America

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

JM, NLS, and RSS designed the study. JM, NLS, and RSS analyzed the data. JM, JZA, NLS, and RSS contributed to writing the paper.