1. Bijl R, DeGraaf R, Hiripi E. et al. The prevalence of treated and untreated mental disorders in five countries. Health Aff. 2003;22:122-133.
2. Kessler R, Berglund P, Demler O, et al. The epidemiology of major depressive disorder: results from the national comorbidity survey replication. JAMA. 2003;289:3095-3105.
3. Stewart W, Ricci J, Chee E, Hahn S, Morganstein D. Cost of lost productive work time among US workers with depression. JAMA. 2003;3135-3144.
4. Aktekin M, Karaman T, Senol Y, Erdem S, Erengin H. Akaydin M. Anxiety, depression and stressful life events among medical students: a prospective study in Antalya, Turkey. Med Educ. 2001;35:6-7.
5. Inam S, Saqib A, Alam E. Prevalence of anxiety and depression among medical students of private university. J Pakistan Med Assoc. 2003;53:44-47.