[1] Univ Southern Calif, Dept Prevent Med, 2001 North Soto St, Los Angeles, CA 90007 USA
[2] Sanford Ctr Biobehav Res, Fargo, ND USA
[3] Univ North Dakota, Sch Med & Hlth Sci, Dept Psychiat & Behav Sci, Grand Forks, ND 58201 USA
[4] North Dakota State Univ, Dept Psychol, Fargo, ND USA
[5] Mississippi State Univ, Dept Psychol, Starkville, MS USA
[6] Duke Univ, Durham, NC 27706 USA