From the Danish Twin Register & Epidemiology (Drs. Gaist, Bak, and Christensen), Institute of Public Health, University of Southern Denmark; Department of Neurology (Drs. Gaist, Madsen, Tsiropoulos, Bak, and Sindrup), Odense University Hospital; Department of Clinical Epidemiology (Dr. Pedersen), Aarhus & Aalborg University Hospital, Denmark; Department of Psychology (Dr. McGue), University of Minnesota, Minneapolis; and Department of Neurology (Dr. Krogh Rasmussen), Hillerød Hospital, Denmark.(2005-02-22時点)
