Funding for this research was provided by:
National Institute of Mental Health (R01MH112628-01, R21MH097022)
Received: 29 March 2018
Accepted: 19 April 2018
First Online: 22 May 2018
Ethics approval and consent to participate
: This study was approved by the institutional review board at the Stanford University and VA Palo Alto Healthcare System, Palo Alto, CA, the City of Philadelphia Department of Public Health Institutional Review Board, Philadelphia, PA, the institutional review board at VA Boston Healthcare System and Boston University, the institutional review board of Massachusetts General Hospital and the Partners Human Research Committee, Somerville, MA, and the institutional review board at University of Pennsylvania, Philadelphia, PA.
: The authors declare that they have no competing interests.
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