Home › Authors › T. Helgason 👤 T. Helgason 5 books Books by T. Helgason Psychological Treatment of Mental Illness 2011 Epidemiology and the prevention of mental disorders 1989 The Long-term treatment of functional psychoses 1985 Methodology in evaluation of psychiatric treatment 1983 Epidemiology of mental disorde Epidemiology of mental disorders in Iceland 1964