Faculty of Health Sciences, University College of Southeast Norway, Drammen, Norway. Electronic address: heidi.ormstad@hbv.no. Ringerike Psychiatric Center, Vestre Viken Hospital Trust, Drammen, Norway. Laboratory of Medical Biochemistry, University of Antwerp, Antwerp, Belgium. NORMENT, KG Jebsen Centre for Psychosis Research, Institute of Clinical Medicine, University of Oslo, Norway; Division of Mental Health and Addiction, Oslo University Hospital, Institute of Clinical Medicine, University of Oslo, Oslo, Norway. Department of Psychiatry, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand; Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand; IMPACT Research Center, Deakin University, Geelong, Australia; Department of Psychiatry, Faculty of Medicine, State University of Londrina, Londrina, Brazil; Department of Psychiatry, Medical University Plovdiv, Plovdiv, Bulgaria.