[1] South African Med Res Council, Alcohol Tobacco & Other Drug Res Unit, Parow, South Africa
[2] Univ Cape Town, Dept Psychiat & Mental Hlth, Fac Hlth Sci, ZA-7700 Rondebosch, South Africa
[3] Univ Washington, Stress & Dev Lab, Seattle, WA 98195 USA
[4] Columbia Univ, New York State Psychiat Inst, Dept Psychiat, Coll Phys & Surg, New York, NY 10027 USA