[1] McGill Univ, Family Med Dept, 5858 Chemin Cote Neiges, Montreal, PQ, Canada
[2] St Marys Lacor Hosp, POB 180, Gulu, Uganda
[3] Int Prevent Res Inst, Allee Claude Debussy, F-69130 Lyon, France
[4] Univ Montreal, 7101 Av Parc, Montreal, PQ H3N 1X9, Canada