Author Contributions: Dr Stukel had 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: Stukel, Lucas, Wennberg.
Analysis and interpretation of data: Stukel,
Drafting of the manuscript: Stukel.
Critical revision of the manuscript for important
intellectual content: Stukel, Lucas, Wennberg.
Statistical analysis: Stukel, Lucas.
Obtained funding: Wennberg.
Study supervision: Stukel.
Financial Disclosures: None reported.
Funding/Support: Funding was provided by the
Robert Wood Johnson Foundation and grant 1PO1-AG19783-01 from the US National
Institute on Aging. The analyses of the Cardiovascular Cooperative Project
data were funded by contract number 500-99-NH01 titled “Utilization
and Quality Control Peer Review Organization for the State of New Hampshire,”
sponsored by the Centers for Medicare & Medicaid Services (formerly the
Health Care Financing Administration), Department of Health and Human Services.
Role of the Sponsor: The Robert Wood Johnson
Foundation and the National Institute on Aging had no role in design and conduct
of the study, collection, data management, analysis and interpretation of
the data, or preparation, review, and approval of the manuscript. The Health
Care Quality Improvement Program initiated by the Centers for Medicare &
Medicaid Services encouraged identification of quality improvement projects
derived from analysis of patterns of care and required no special funding
on the part of this contractor.
Disclaimer: The content of this publication
does not necessarily reflect the views or policies of the Department of Health
and Human Services, the Centers for Medicare & Medicare Services, or the
National Institute on Aging, nor does mention of trade names, commercial products,
or organizations imply endorsement by the US government.
Acknowledgment: We acknowledge the insightful
contributions of Elliott Fisher, David Alter, Dan Gottlieb, and Doug Staiger.
We thank Dan Gottlieb for assistance with data analysis and Nancy MacCallum
for assistance with manuscript preparation.