first phase of therapy focuses on symptoms and relieving the distressing aspects of the condition, ensuring the safety of the individual, improving the patient's capacity to form and maintain healthy relationships, and improving general daily life functioning. Comorbid disorders such as substance use disorder and eating disorders are addressed in this phase of treatment. The second phase focuses on stepwise exposure to traumatic memories and prevention of re-dissociation. The final phase focuses on reconnecting the identities of disparate alters into a single functioning identity with all its memories and experiences intact. A study was conducted to develop an "expertise-based prognostic model for the treatment of complex post-traumatic stress disorder (PTSD) and dissociative identity disorder (DID)". Researchers constructed a two-stage survey and factor analyses performed on the survey elements found 51 factors common to complex PTSD and DID. The authors concluded from their findings: "The model is supportive of the current phase-oriented treatment model, emphasizing the strengthening of the therapeutic relationship and the patient's resources in the initial stabilization phase. Further research is needed to test the model's statistical and clinical validity." Prognosis Little is known about prognosis of untreated DID. It rarely, if ever, goes away without treatment, but symptoms may resolve from time to time or wax and wane spontaneously. Patients with mainly dissociative and post-traumatic symptoms face a better prognosis than those with comorbid disorders or those still in contact with abusers, and the latter groups often face lengthier and more difficult treatment. Suicidal ideation, suicide attempts, and self-harm also may occur. Duration of treatment can vary depending on patient goals, which can range from merely improving inter-alter communication and cooperation, to reducing inter-alter amnesia, to integration of all alters, but generally takes years. Epidemiology General According to the American Psychiatric Association, the 12-month prevalence of DID among adults in the US is 1.5%, with similar prevalence between women and men. Population prevalence estimates have been described to widely vary, with some estimates of DID in inpatient settings suggesting 1-9.6%." Reported rates in the community vary from 1% to 3% with higher rates among psychiatric patients. As of 2017, evidence suggested a prevalence of DID of 2–5% among psychiatric inpatients, 2–3% among outpatients, and 1% in the general population, with rates reported as high as 16.4% for teenagers in psychiatric outpatient services. Dissociative disorders in general have a prevalence of 12.0%–13.8% for psychiatric outpatients. As of 2012, DID