a mere 13% improvement rate. Prognosis Empirical studies have found that the prognosis for conversion disorder varies widely, with some cases resolving in weeks, and others enduring for years or decades. There is also evidence that there is no cure for conversion disorder, and that although patients may go into remission they can relapse at any point. Furthermore, many patients can get rid of their symptoms with time, treatments and reassurance. Epidemiology Frequency Information on the frequency of conversion disorder in the West is limited, in part due to the complexities of the diagnostic process. In neurology clinics, the reported prevalence of unexplained symptoms among new patients is very high (between 30 and 60%). However, diagnosis of conversion typically requires an additional psychiatric evaluation, and since few patients will see a psychiatrist it is unclear what proportion of the unexplained symptoms are actually due to conversion. Large scale psychiatric registers in the US and Iceland found incidence rates of 22 and 11 newly diagnosed cases per 100,000 person-years, respectively. Some estimates claim that in the general population, between 0.011% and 0.5% of the population have conversion disorder. Culture Although it is often thought that the frequency of conversion may be higher outside of the West, perhaps in relation to cultural and medical attitudes, evidence of this is limited. A community survey of urban Turkey found a prevalence of 5.6%. Many authors have found occurrence of conversion to be more frequent in rural, lower socio-economic groups, where technological investigation of patients is limited and people may know less about medical and psychological concepts. Gender Historically, the concept of 'hysteria' was originally understood to be a condition exclusively affecting women, though the concept was eventually extended to men. In recent surveys of conversion disorder (formerly classified as "hysterical neurosis, conversion type"), females predominate, with between two and six female patients for every male but some research suggests this gender disparity may be confounded by higher rates of violence against women. Age Conversion disorder may present at any age but is rare in children younger than ten or in the elderly. Studies suggest a peak onset in the mid-to-late 30s. History The first evidence of functional neurological symptom disorder dates back to 1900 BC, when the symptoms were blamed on the uterus moving within the female body. The treatment varied "depending on the position of the uterus, which must be forced to return