[1] Univ Bologna, Dept Pharmacol, Interuniv Res Ctr Pharmacoepidemiol, I-40126 Bologna, Italy
[2] Univ So Denmark, Res Unit Gen Practice, Odense, Denmark
[3] Univ So Denmark, Dept Clin Pharmacol, Odense, Denmark
[4] Karolinska Inst, Div Clin Pharmacol, WHO, Collaborating Ctr Drug Utilizat Res, SE-14186 Stockholm, Sweden
[5] Huddinge Univ Hosp, Clin Pharmacol Serv, SE-14186 Stockholm, Sweden