professionals, made difficult due to the lack of specific and reliable criteria for diagnosing DID as well as a lack of prevalence rates due to the failure to examine systematically selected and representative populations. Differential diagnoses People with DID are diagnosed with five to seven comorbid disorders on average – much higher than other mental illnesses. Due to overlapping symptoms, the differential diagnosis includes schizophrenia, normal and rapid-cycling bipolar disorder, epilepsy, borderline personality disorder, and autism spectrum disorder. Delusions or auditory hallucinations can be mistaken for speech by other personalities. Persistence and consistency of identities and behavior, amnesia, measures of dissociation or hypnotizability and reports from family members or other associates indicating a history of such changes can help distinguish DID from other conditions. A diagnosis of DID takes precedence over any other dissociative disorders. Distinguishing DID from malingering is a concern when financial or legal gains are an issue, and factitious disorder may also be considered if the person has a history of help or attention-seeking. Individuals who state that their symptoms are due to external spirits or entities entering their bodies are generally diagnosed with dissociative disorder not otherwise specified rather than DID due to the lack of identities or personality states. Most individuals who enter an emergency department and are unaware of their names are generally in a psychotic state. Although auditory hallucinations are common in DID, complex visual hallucinations may also occur. Those with DID generally have adequate reality testing; they may have positive Schneiderian symptoms of schizophrenia but lack the negative symptoms. They perceive any voices heard as coming from inside their heads (patients with schizophrenia experience them as external). In addition, individuals with psychosis are much less susceptible to hypnosis than those with DID. Difficulties in differential diagnosis are increased in children. DID must be distinguished from, or determined if comorbid with, a variety of disorders including mood disorders, psychosis, anxiety disorders, PTSD, personality disorders, cognitive disorders, neurological disorders, epilepsy, somatoform disorder, factitious disorder, malingering, other dissociative disorders, and trance states. An additional aspect of the controversy of diagnosis is that there are many forms of dissociation and memory lapses, which can be common in both stressful and nonstressful situations and can be attributed to much less controversial diagnoses. Individuals faking or mimicking DID due to factitious disorder will typically exaggerate symptoms (particularly when observed), lie, blame bad behavior on symptoms and often show