6 Clinical Neuropsychiatry (2006) 3, 1, © 2006 Giovanni Fioriti Editore s.r.l. 6-22 RECEIVED AUGUST 2005, ACCEPTED JANUARY 2006 Summary This article reviews the existing literature on early screening efforts and preventive interventions of major depressive disorder in three developmental groups: children and adolescents, adults, and elderly persons. Risk factors for the development of depression are identified across the lifespan. Psychometrically sound screening instruments are available, although such measures have somewhat limited ability to predict future depression. Extensive variability in methodology, sampling, and research design exist in preventive interventions. In general, there is evidence demonstrating that interventions are more effective in preventing depression at the clinical level rather than the subsyndromal level for adult populations. Also, selective interventions are more effective than universal interventions in preventing major depressive disorder. More research is focused on and generally found support for cognitive- behavioral prevention programs than any other type of interventions. This review highlights the complexity and multidimensional nature of major depressive disorder in terms of early detection and interventions aimed at preventing major depression across the lifespan. Key Words: Depression  Screening  Prevention  Lifespan Declaration of Interest: none Huynh-Nhu Le, The George Washington University Rhonda C. Boyd, University of Pennsylvania School of Medicine and Childrens Hospital of Philadelphia Corresponding Author Huynh-Nhu Le, Department of Psychology, The George Washington University. 2125 G St., NW. Washington, DC 20052. E- mail address: hnle@gwu.edu PREVENTION OF MAJOR DEPRESSION: EARLY DETECTION AND EARLY INTERVENTION IN THE GENERAL POPULATION Huynh-Nhu Le, Rhonda C. Boyd Introduction Prevalence and Course Major depressive disorder (MDD) is a chronic and disabling psychiatric disorder. MDD, or major depres- sion, is the most common disorder of all mental ill- nesses (U.S. Department of Health 2000). In the gen- eral population, lifetime prevalence of MDD is 12.8% in Europe (ESEMed/MHEDEA 2000 Investigators 2004a) and 16.2% in the United States (Kessler et al. 2003). Twelve-month prevalence rates of MDD are 3.9% and 6.6% in Europe and U.S., respectively. Ac- cording to the World Health Organization (2002), ma- jor depression has been ranked as the fourth greatest burden of disease worldwide and is expected to become the second by 2020. MDD is the greatest cause of dis- ability throughout the world (Murray and Lopez 1996). Moreover, MDD typically has a chronic course (Moller et al. 2003, Rost et al. 2002). The lifetime risk of recur- rence increases to 50% after one episode of major de- pression, 70% after two episodes, and 90% after three episodes (Depression Guideline Panel 1993, Judd 1997), and 12% remain depressed for five or more years (Angst 1988, Keller 1992). Risk of relapse also in- creases with recurrences (Belsher 1988), even follow- ing treatment (Gortner 1998). MDD is highly comorbid, especially with anxiety disorders, substance use disor- ders, and impulse control disorders (Kessler et al. 2003). Major depression can also be fatal and is commonly associated with suicide (Institute of Medicine 2002). Detection and Intervention Despite the seriousness of this disease, major de- pression is under-recognized and under-treated. As many as 50% of cases of major depression are not de- tected in primary care settings (Dorwick and Buchan 1995). Even when diagnosed, few receive treatment (Kessler et al. 2005). For example, data from the Euro- pean Study of the Epidemiology of Mental Disorders revealed that only 21.2% of individuals with major depression received any antidepressant medication within the previous 12-month period (ESEMed/ MHEDEA 2000 Investigators 2004b). In addition, in- adequate treatment, limited responsiveness to treatment, and lack of follow-up care are common (American Psy- chiatric Association 2000, Kessler et al. 2005, Parikh et al. 1999). These limitations in treatment exist de-