aDepartment of Epidemiology, Faculty of Medicine, Prince of Songkla University, Hat Yai, Songkhla, 90110

bDepartment of Psychiatry, Faculty of Medicine, Chulalongkorn University

cDepartment of Psychiatry, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok

dSrithanya Psychiatric Hospital, Nonthaburi, Thailand

Correspondence to Sawitri Assanangkornchai, Department of Epidemiology, Faculty of Medicine, Prince of Songkla University, Hat Yai, Songkhla, 90110 Thailand. Tel: +66 7445 1165 6; e-mail: [email protected]