Other specified dissociative disorder (OSDD) is a mental health diagnosis for pathological dissociation that matches the DSM-5 criteria for a dissociative disorder, but does not fit the full criteria for any of the specifically identified subtypes, which include dissociative identity disorder, dissociative amnesia, and depersonalization/derealization disorder, and the reasons why the previous diagnoses were not met are specified. "Unspecified dissociative disorder" is given when the clinician does not give a reason. The International Statistical Classification of Diseases and Related Health Problems (ICD-10) refers to the diagnosis as "Other dissociative and conversion disorders". Under the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM), it was known as "Dissociative disorder not otherwise specified" (DDNOS). Examples of OSDD include chronic and recurrent syndromes of mixed dissociative symptoms, identity disturbance due to prolonged and intense coercive persuasion, disorders similar to dissociative identity disorder, acute dissociative reactions to stressful events, and dissociative trance. OSDD is the most common dissociative disorder and is diagnosed in 40% of dissociative disorder cases. It is often co-morbid with other mental illnesses such as complex posttraumatic stress disorder, major depressive disorder, generalized anxiety disorder, personality disorders, substance use disorders, and eating disorders. There are currently no available drugs that treat dissociative symptoms directly; however, dissociative conditions appear to respond well to psychotherapy. Evolution OSDD was officially adopted in the DSM-V, which was published in 2013, alongside Unspecified Dissociative Disorder to replace DDNOS. Criteria There are currently four examples of OSDD given in the DSM. OSDD is a "catch-all" category for any presentation that is abnormal but does not meet the diagnostic criteria for any of the dissociative disorders, and therefore the examples given are not the only presentations of OSDD possible. OSDD is only diagnosed when it is known that another dissociative disorder is not present; if the diagnosis is still being clarified, or if there is not enough time to make an informed diagnosis (such as in an emergency room setting), a diagnosis of unspecified dissociative disorder may be given. It is worth noting that a person will not be diagnosed with "OSDD type 4" (for example); instead they will simply be diagnosed with OSDD. The diagnosing clinician may specify in the client's file that the diagnosis is "OSDD (dissociative trance)", but in general the simple diagnosis of OSDD will be given. OSDD type 1 OSDD-1 is diagnosed when a person is experiencing sub-threshold dissociative