[1] Univ Penn, Dept Psychiat, Philadelphia, PA 19104 USA
[2] Univ Iowa, Dept Psychiat, Iowa City, IA 52242 USA
[3] Johns Hopkins Univ, Dept Psychiat, Baltimore, MD USA
[4] Rush Presbyterian St Lukes Med Ctr, Dept Psychiat, Chicago, IL 60612 USA
[5] Columbia Univ, Coll Phys & Surg, Dept Psychiat, New York, NY 10027 USA
[6] NY State Psychiat Inst, New York, NY USA
[7] MRC BSU, Cambridge, England
[8] Univ Wales Coll Med, Dept Psychol Med, Cardiff CF4 4XN, S Glam, Wales