1. American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders, 4th ed. Washington, DC: American Psychiatric Association, 1994.
2. Kessler RC, Berglund P, Demler O, et al. The epidemiology of major depressive disorder: results from the National Comorbidity Survey Replication (NCS-R). JAMA 2003; 289(23):3095–105.
3. WHO. The World Health Report 2001. Mental Health: New Understanding, New Hope. Geneva, Switzerland: World Health Organization, 2001.
4. Murray CJL, Lopez, AD, eds. Global burden of disease: a comprehensive assessment of mortality and disability from diseases, injuries and risk factors in 1990 and projected to 2020. Boston, MA: Harvard University Press, 1996.
5. Steffens DC, Skoog I, Norton MC, et al. Prevalence of depression and its treatment in an elderly population: the Cache County study. Arch Gen Psychiatry 2000; 57(6):601–7.