[1] RAND Corp, 1776 Main St,POB 2138, Santa Monica, CA 90407 USA
[2] Univ Southern Calif, Suzanne Dworak Peck Sch Social Work, Los Angeles, CA 90007 USA
[3] Univ Southern Calif, USC Inst Addict Sci, Los Angeles, CA 90007 USA
[4] RAND Corp, Boston, MA USA
[5] Univ Southern Calif, Dept Prevent Med, Keck Sch Med, Los Angeles, CA 90007 USA