Author Contributions: Dr Tangen had full 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: Klein, Thompson, Tangen, Crowley, P. Goodman, Minasian, Ford, Parnes, Lieber, Walther, Klotz, Lippman, G. Goodman, Baker.
Acquisition of data: Klein, Thompson, Tangen, Crowley, Lucia, P. Goodman, Parsons, Chin.
Analysis and interpretation of data: Klein, Thompson, Tangen, Crowley, P. Goodman, Minasian, Ford, Karp, Klotz, Darke, Lippman, G. Goodman, Meyskens.
Drafting of the manuscript: Klein, Thompson, Tangen, P. Goodman, Lieber, Klotz, G. Goodman, Baker.
Critical revision of the manuscript for important intellectual content: Klein, Thompson, Tangen, Crowley, Lucia, P. Goodman, Minasian, Ford, Parnes, Karp, Walther, Parsons, Chin, Darke, Lippman, Meyskens, Baker.
Statistical analysis: Tangen, Crowley, P. Goodman, Darke.
Obtained funding: Klein, Thompson, Lippman, Baker.
Administrative, technical, or material support: Klein, Thompson, Lucia, Minasian, Parnes, Lieber, Walther, Parsons, Chin, Lippman.
Study supervision: Thompson, Crowley, P. Goodman, Minasian, Ford, Klotz, Lippman, G. Goodman, Baker.
Conflict of Interest Disclosures: All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr Thompson reported receiving research support from the National Cancer Institute for a randomized controlled trial testing finasteride against placebo, both of which are supplied by Merck. Dr Gaziano reported receiving grant support (to his institution) from Wyeth (now Pfizer) in the form of vitamin and placebo pills and packaging. Dr Karp reported receiving grants to his institution from Pfizer. Dr Klotz reported receiving travel support for meetings from sanofi-aventis, Merck, and AstraZeneca and research support for investigator-initiated trials from Abbott and GlaxoSmithKline, and institutional grants pending. Dr Chin reported receiving consultancy fees from Janssen, Amgen, Novartis, and Firmagon; receiving payment for lectures from Firmagon; and payment for development of educational presentations from AstraZeneca, Novartis, and Firmagon. Dr Meyskens reported being a co-founder of Cancer Prevention Pharmaceuticals. Dr Baker reported board membership for Merck for which he receives no compensation. Otherwise there were no other conflicts of interest disclosed.
Funding/Support: This work was supported in part by Public Health Service Cooperative Agreement grant CA37429 awarded by the National Cancer Institute, National Institutes of Health, Department of Health and Human Services, and in part by the National Center for Complementary and Alternative Medicine (National Institutes of Health). Study agents and packaging were provided by Perrigo Co, Allegan, Michigan; Sabinsa Corp, Piscataway, New Jersey; Tishcon Corp, Westbury, New York; and DSM Nutritional Products Inc, Parsipanny, New Jersey.
Disclaimer: Dr Gaziano, a contributing editor for JAMA, was not involved in the editorial review of or the decision to publish this article.
Role of the Sponsor: This work was supported by the National Institutes of Health, primarily the National Cancer Institute (NCI) and the National Center for Complementary and Alternative Medicine. Representatives from the National Institutes of Health (NCI) participated in design, oversight, and reporting of this study.
Online-Only Material: The Author Video Interview is available here.
This article was corrected for errors on October 11, 2011.