[1] Univ Torino, Dept Clin & Biol Sci, Reg Gonzole 10, I-10043 Turin, Italy
[2] ASL TO3, Piedmont Ctr Drug Addict Epidemiol, Turin, Italy
[3] United Nat Off Drugs & Crime, Project Off, Lagos, Nigeria
[4] Univ Jos, Jos, Nigeria
[5] Univ Coll, Fac Educ Hlth & Social Work, Ghent, Belgium
[6] Piedmont Ctr Drug Addict Epidemiol, Tech Support Team, Turin, Italy
[7] Univ Coll, Ghent, Belgium
[8] Fed Minist Educ, Abuja, Nigeria
[9] Natl Drug Law Enforcement Agcy, Lagos, Nigeria
[10] Natl Agcy Food & Drug Adm & Control, Abuja, Nigeria