Study concept and design: Cohen.
Acquisition, analysis, or interpretation of data: All authors.
Drafting of the manuscript: Cohen.
Critical revision of the manuscript for important intellectual content: All authors.
Statistical analysis: Maller, DeSouza.
Obtained funding: Cohen.
Administrative, technical, or material support: Maller, Neal-Kababick.
Study supervision: Cohen.
Conflict of Interest Disclosures: The authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Mr Maller reported receiving personal fees from NY State Senator Jeffrey Klein and SSP Nutrition outside of the submitted work. Mr Neal-Kababick reported being the vice chair of the US Pharmacopeia expert panel on Adulteration of Dietary Supplements with Drugs and Drug Analogues; reported being a co-owner of Flora Research Laboratories (some of the clients are dietary supplement manufacturers); and reported serving as an expert witness in cases involving the investigation of quality issues in the production of dietary supplements. No other disclosures were reported.
Funding/Support: This research was supported in part by a grant from Consumers Union.
Role of the Funder/Sponsor: Consumers Union had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.
Additional Contributions: We acknowledge Mercy Imahiyerobo, MPH, JD (Harvard School of Public Health), for her assistance in identifying recalled supplements; she was not compensated for her contribution. Ms Imahiyerobo is now with a private law firm.
Correction: This article was corrected on November 4, 2014, to fix the name of the study funder.