Study concept and design: Silverman, Goldenberg, Magis-Rodriguez, Raj.
Acquisition, analysis, or interpretation of data: Silverman, Servin, Goldenberg, Ritter, Brouwer.
Drafting of the manuscript: Silverman, Servin, Ritter.
Critical revision of the manuscript for important intellectual content: Silverman, Goldenberg, Magis-Rodriguez, Ritter, Raj, Brouwer.
Statistical analysis: Silverman, Ritter.
Obtained funding: Silverman, Goldenberg, Brouwer.
Administrative, technical, or material support: Silverman, Servin, Goldenberg, Brouwer.
Study supervision: Silverman, Magis-Rodriguez.
Conflict of Interest Disclosures: The authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest and none were reported.
Funding/Support: The study was supported via funding from the National Institute on Drug Abuse (grant R01DA033194 awarded to Dr Silverman and grant R01DA028692 awarded to Dr Brouwer) and the University of California–San Diego AIDS Research Institute via the National Institute of Allergy and Infectious Diseases (grant P30A136214).
Role of the Funder/Sponsor: The funders 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 thank Leah Gordon, MPH, and Sabrina Boyce, MPH, for contributing to the collection and analysis of the data and revision of the manuscript. Both were compensated as employees of the University of California–San Diego School of Medicine. We also thank Hugo Staines Orozco, MD (Universidad Autónoma de Ciudad Juarez), and Gustavo Martinez Mendizábal, MD (Federación Mexicana de Asociaciones Privadas), who provided assistance with data collection. Neither received compensation for their contributions.