[1] Yale Univ, Sch Med, Ctr Child Study, New Haven, CT 06520 USA
[2] Univ Nacl Autonoma Mexico, Mexico City 04510, DF, Mexico
[3] Hosp Espanol, Mexico City, DF, Mexico
[4] Connecticut Mental Hlth Ctr, New Haven, CT USA
[5] Yale Sch Epidemiol & Publ Hlth, New Haven, CT USA