[1] VA Cent Western Massachusetts Healthcare Syst, Leeds, MA 01053 USA
[2] Univ Massachusetts, Sch Med, Dept Populat & Quantitat Hlth Sci, Worcester, MA 01655 USA
[3] Univ Massachusetts, Sch Med, Dept Psychiat, Worcester, MA 01655 USA
[4] UT Hlth Sci Ctr, Dept Psychiat, San Antonio, TX USA
[5] VA New England Hlth Care Syst, Bedford, MA USA
[6] Durham VA Healthcare Syst, Durham, NC USA