1. School of Medicine, University of California, San Fransisco, California, USA
2. Opioid Treatment Outpatient Program, Division of Substance Abuse and Addiction Medicine, Department of Psychiatry, University of California, San Francisco, California, USA
3. Division of General Internal Medicine, Department of Medicine, University of California, San Francisco, California, USA
4. Department of Humanities and Social Sciences, University of California, San Francisco, California, USA