High heterogeneity and low reliability in the diagnosis of major depression will impair the development of new drugs

SUMMARY Major depressive disorder is a common diagnosis associated with a high burden of disease that has proven to be highly heterogeneous and unreliable. Treatments currently available demonstrate limited efficacy and effectiveness. New drug development is urgently required but is likely to be hindered by diagnostic limitations. DECLARATIONS OF INTEREST D.J.C. has received grants and personal fees from Eli Lilly, Janssen-Cilag, Roche, Allergen, Bristol-Myers Squibb, Pfizer, Lundbeck, AstraZeneca, Hospira, Organon, Sanofi-Aventis, and Wyeth during the writing of this review. C.P. has received grant support from Janssen-Cilag, Eli Lilly, Hospira (Mayne), AstraZeneca, and received honoraria for consultancy to Janssen-Cilag, Eli Lilly, Hospira (Mayne), AstraZeneca, Pfizer, Schering Plough, and Lundbeck. Over the past 2 years he has participated on advisory boards for Janssen-Cilag and Lundbeck, and received honoraria for talks presented at educational meetings organised by AstraZeneca, Janssen-Cilag and Lundbeck. M.H. has received personal fees or grants from Lundbeck, AstraZeneca and Servier during the writing of this review. A.H.Y. reports personal fees from Lundbeck, Sunovion, AstraZeneca and Janssen outside the submitted work. I.P.E. has received personal fees or grants from Lundbeck, AstraZeneca, and Abbvie during the writing of this review. COPYRIGHT AND USAGE © The Royal College of Psychiatrists 2015. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) licence.