[1] Univ Calif Los Angeles, David Geffen Sch Med, Dept Family Med, Los Angeles, CA 90095 USA
[2] Univ Calif Los Angeles, Semel Inst Neurosci & Human Behav, Integrated Substance Abuse Programs, Los Angeles, CA 90025 USA
[3] Univ Calif Los Angeles, David Geffen Sch Med, Dept Biostat, Los Angeles, CA 90024 USA
[4] Univ Calif Los Angeles, David Geffen Sch Med, Dept Med, Los Angeles, CA 90024 USA
[5] Univ Calif Los Angeles, David Geffen Sch Med, Dept Psychiat & Biobehav Sci, Los Angeles, CA 90024 USA