This concise guide provides psychiatrists (including trainees) and general practitioners with a comprehensive overview of the most clinically relevant assessment scales and tools in order to assist with and enhance diagnostic outcomes in depression.

Depression is one of the most common mood disorders across the globe, with a lifetime prevalence across all people of 8-10%. Despite being relatively common, depression remains severely underdiagnosed across all age groups and nationalities.

George Alexopoulos, MD, is SP Tobin and AM Cooper Professor of Psychiatry, founder and director of the Weill-Cornell Institute of Geriatric Psychiatry, and director of the Advanced Center for Interventions and Services Research in Geriatric Mood Disorders at Cornell University, New York, USA. Dr Alexopoulos received his MD from the National University of Athens, Greece, trained at New Jersey Medical School, and completed his psychiatric residency at Cornell University Medical College, where he completed a research fellowship in Psychobiology. Dr Alexopoulos has made fundamental contributions to the study of the biology of late-life depression including identifying brain mechanisms contributing to poor response to antidepressant drugs, development of new treatments for patients with depression and severe medical illnesses, and improving the practice model for the identification and treatment of depression in primary care. Dr Alexopoulos has served on the Board of Scientific Counselors of the National Institute of Mental Health and has received four consecutive Center Grant Awards from the National Institute of Mental Health and numerous individual grants. He has been the Director of the T32 NIMH Research Fellowship in Geriatric Mood Disorders since 1989. Dr Alexopoulos is a fellow of the American College of Neuropsychopharmacology, American College of Psychiatrists (ACP), and a Distinguished Life Fellow of the American Psychiatric Association (APA). He has received several awards, including an APA Presidential Commendation, the Research Award of the International College of American College of Geriatric Psychoneuropharmacology, the APA Greenberg Award, the ACP Geriatric Research Award, the Joseph Zubin Research Award of the American Psychopathological Association, the APA Distinguished Psychiatrist Lecturer Award, and the Senior Investigator's Award of the American Association for Geriatric Psychiatry. Dr Alexopoulos is the editor of the International Journal of Geriatric Psychiatry (Western Hemisphere) and has published more than 400 articles and book chapters.

Siegfried Kasper, MD is Professor of Psychiatry and Chairman of the Department of Psychiatry and Psychotherapy at the Medical University of Vienna, Austria. Dr Kasper serves/served on the executive committees and advisory boards of several national and international societies, such as the European College of Neuropsychopharmacology (ECNP) and the European Psychiatric Association (EPA). He has been elected to the Executive Committee of the International College of Neuropsychopharmacology (CINP) for the period of 2012 to 2016. He is Chair of the World Psychiatric Association (WPA) Section of Pharmacopsychiatry, President of the Austrian Society of Drug Safety in Psychiatry (ÖAMSP), and Past-President of the Austrian Society of Neuropsychopharmacology and Biological Psychiatry (ÖGPB). Dr Kasper is an Honorary Member of the Czech and Romanian Societies of Neuropsychopharmacology, the Hungarian Psychiatric Association, and a Fellow of the Royal College of Psychiatrists (UK) and Ukrainian Association of Psychiatry. Dr Kasper has been President of the 10th ECNP Congress, Chairman of the Local Organizing Committee of the WPA Thematic Conference, and Co-Chair of the Local Organizing Committee of the WFSBP Congress. In 2009, he was President of the WFSBP Congress in Paris. In 2005, he was appointed Honorary Professor at the University of Hong Kong, China. From 2005 to 2009, Dr Kasper was President of the World Federation of Societies of Biological Psychiatry (WFSBP) and was appointed as Honorary President of the WFSBP in 2013. Dr Kasper serves on editorial boards of numerous learned journals, including Lancet Psychiatry, Journal of Clinical Psychiatry, CNS Spectrums, Journal of Affective Disorders, Pharmacopsychiatry, European Archives of Psychiatry, and Neuroscience. He is Editor-in-Chief of the World Journal of Biological Psychiatry and the International Journal of Psychiatry in Clinical Practice, and Field Editor of the International Journal of Neuropsychopharmacology. Dr Kasper has published over 1000 ISI-listed publications and more than 200 book chapters.

Hans-Jürgen Möller, MD, is Emeritus Professor at the Department of Psychiatry, Ludwig Maximilian University, Munich, Germany, where he was Chairman and Professor of Psychiatry from 1994 to 2012. He has worked in the field of psychiatry for more than 40 years. After obtaining his Doctor of Medical Science in 1972, he completed postgraduate training in psychiatry at the Max Planck Institute of Psychiatry in Munich. From 1980 to 1988 he was Professor of Psychiatry at Munich Technical University and from 1988 to 1994 full Professorof Psychiatry and Chairman of the Department of Psychiatry at the University of Bonn. His main scientific contributions include clinical and neurobiological research into psychiatry, schizophrenia and depression and clinical psychopharmacology. He has written and coauthored over 1,100 publications, including numerous original articles (Hirsch Factor 68) and several books. He is co-editor of European Archives of Psychiatry and Clinical Neuroscience and Psychopharmakotherapie, founding editor and former chief editor of The World Journal of Biological Psychiatry and holds positions on the editorial boards of several national and international psychiatric journals. He has been a member of the executive committees of many national and international psychiatric societies. He was President of the World Federation of Societies of Biological Psychiatry (WFSBP), President of the European Psychiatric Association (EPA) and Chairman of the World Psychiatric Association (WPA) Section on Pharmacopsychiatry. Currently, he is Past-President of the Collegium Internationale Neuro-Psychopharmacologicum (CINP). He has received numerous awards including the WPA Jean Delay Prize and the WFSBP Lifetime Achievement Award.

Carmen Moreno, MD, PhD, is a Child Psychiatrist and Associate Professor of the Gregorio Marañón Psychiatry Department, Complutense University School of Medicine, Madrid, Spain. Dr. Moreno completed her MD and PhD degrees at Autónoma University and Complutense University in Madrid, and a Research Fellowship in Child and Adolescent Psychiatry at Columbia University, New York, USA. Dr. Moreno has focused her career on early-onset psychiatric disorders, mainly affective and psychotic disorders, and recently, also other neurodevelopmental disorders. She is recognized by her studies in raising awareness of the misdiagnosis of bipolar disorder in children and adolescents. She has authored more than 30 peer-reviewed publications. Her efforts are now focused on understanding the role of inflammation and oxidative stress on early-onset psychiatric disorders, and towards development of new treatment interventions.