The questionable reliability of major depressive disorder, unchanged from DSM-IV, is obviously a problem. Major depressive disorder has always been problematic because its criteria encompass a wide range of illness, from gravely disabled melancholic patients to many individuals in the general population who do not seek treatment. Although symptom severity on the Hamilton Depression Rating Scale distinguishes those patients who respond more specifically to pharmacotherapy, the DSM-IV criteria do not capture that distinction (6). A second problem not resolved by the DSM-IV criteria is the common co-occurrence of anxiety, which markedly diminishes the effects of antidepressant treatment (7). The DSM-5 work group decided not to change the criteria for major depressive disorder from DSM-IV and instead created other diagnoses for the mixture between anxiety and depression. However, these efforts did not improve the poor reliability of DSM-IV depression; “mixed anxiety and depression” has a kappa of 0. Clinicians often use patients’ self-rating on the Beck Depression Inventory as an indicator of severity. The dimensional cross-cutting domains in this field trial similarly rely on self-rating (5). For depression there are two domains and the intraclass correlations, which are similar to the kappa statistic, for adult patients rating and rerating themselves and for parents rating their children; all exceed 0.6. Future revisions will likely need to integrate the many factors—patient self-ratings, cognitive biases, co-occurring anxiety, and vegetative symptoms—that guide treatment selection, prognosis, and assessment of suicide risk.