Neurosciences Department (Solmi, Miola), Padua Neuroscience Center (Solmi), Department of General Psychology (Poddighe), and Department of Philosophy, Sociology, Education, and Applied Psychology (Delogu), University of Padua, Italy; Early Psychosis: Interventions and Clinical Detection (EPIC) Lab, Department of Psychosis Studies, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London (Solmi, Fusar-Poli); Psychiatry Department, University of Ottawa, Ottawa (Fiedorowicz); Department of Clinical Medicine, Faculty of Health Sciences, UiT-Arctic University of Norway, Tromsø (Høye); Division of Mental Health and Substance Abuse, University Hospital of North Norway, Tromsø (Høye); Center for Clinical Documentation and Evaluation (SKDE), Tromsø (Høye, Heiberg); Physiotherapy Department, South London and Maudsley NHS Foundation Trust, and Department of Psychological Medicine, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London (Stubbs); Cambridge Centre for Sport and Exercise Science, Anglia Ruskin University, Cambridge, U.K. (Smith); Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, and School of Medical Sciences, Örebro University, Örebro, Sweden (Larsson); Department of Cardiology, Aalborg University Hospital, Aalborg, Denmark, and Department of Clinical Sciences, Lund University, Lund, Sweden (Attar); Department of Psychiatry, Aalborg University Hospital, and Department of Clinical Medicine, Aalborg University, Aalborg, Denmark (Nielsen); Centre for Innovation in Mental Health–Developmental Lab, School of Psychology, University of Southampton, and NHS Trust, Southampton, U.K. (Cortese); Hassenfeld Children's Hospital at NYU Langone, New York University Child Study Center, New York (Cortese); Division of Psychiatry and Applied Psychology, School of Medicine, University of Nottingham, Nottingham, U.K. (Cortese); Department of Pediatrics, Yonsei University College of Medicine, Seoul, Korea (Shin); National Institute for Health Research, Maudsley Biomedical Research Centre, and OASIS Service, South London and Maudsley NHS Foundation Trust, London (Fusar-Poli); Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy (Fusar-Poli); Division of Psychology and Mental Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, U.K. (Firth); NICM Health Research Institute, Western Sydney University, Westmead, Australia (Firth); Department of Psychiatry, University of British Columbia, Vancouver (Yatham); Department of Psychiatry, University of Toronto, and Centre for Addiction and Mental Health, Toronto (Castle, Seeman); IMPACT (Innovation in Mental and Physical Health and Clinical Treatment) Strategic Research Centre, School of Medicine, Barwon Health, Deakin University, Geelong, Australia (Carvalho); Department of Child and Adolescent Psychiatry, Psychosomatics, and Psychotherapy, Charité University Medicine Berlin, Berlin (Correll); Department of Psychiatry, Zucker Hillside Hospital, Northwell Health, Glen Oaks, N.Y. (Correll); and Department of Psychiatry and Molecular Medicine, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, N.Y. (Correll)