Dissociative identity disorder is known only in the United States of America.
Dissociative identity disorder -LRB- DID -RRB- , also known as multiple personality disorder -LRB- MPD -RRB- , is a mental disorder characterized by at least two distinct and relatively enduring identities or dissociated personality states .. mental disorder. mental disorder. identities. Identity ( social science ). personality. personality. These states alternately show in a person 's behavior , accompanied by memory impairment for important information not explained by ordinary forgetfulness .. These symptoms are not accounted for by substance abuse , seizures , or other medical conditions , nor by imaginative play in children .. substance abuse. substance abuse. Dissociative symptoms range from common lapses in attention , becoming distracted by something else , and daydreaming , to pathological dissociative disorders .. dissociative disorders. dissociative disorders. Symptoms vary over time .. Dissociative disorders , including DID , have been attributed to disruptions in memory caused by trauma or other forms of stress .. trauma. Psychological trauma. Research on this hypothesis has been characterized by poor methodology .. hypothesis. hypothesis. methodology. Scientific method. An alternative hypothesis is that DID is a by-product of techniques employed by some therapists , especially those using hypnosis , and disagreement between the two positions is characterized by intense debate .. hypothesis. hypothesis. techniques employed by some therapists. Iatrogenesis#Psychology. hypnosis. hypnosis. DID is one of the most controversial psychiatric disorders , with no clear consensus on diagnostic criteria or treatment .. No systematic , empirically supported definition of `` dissociation '' exists .. empirically supported. Empirical research. dissociation. Dissociation ( psychology ). Diagnosis is often difficult , as the entity is frequently associated with other mental disorders .. Differential diagnosis should consider malingering if the individual 's principal concern is with financial or forensic gain or with the avoidance of obligations ; and factitious disorder , if the individual 's principal concern is with assuming a patient role .. Differential diagnosis. Differential diagnosis. malingering. malingering. factitious disorder. factitious disorder. patient. patient. It is generally believed that DID rarely resolves spontaneously .. In general , the prognosis is poor , especially for those with comorbid disorders .. There is little systematic data on rates of the condition .. It is believed to affect between 1 % and 3 % of the general population , and between 1 % and 5 % in inpatient groups in Europe and North America .. inpatient. inpatient. DID is diagnosed more frequently in North America than in the rest of the world , and is diagnosed three to nine times more often in females than in males .. Rates of diagnoses increased greatly in the latter half of the 20th century , along with the number of identities -LRB- often referred to as `` alters '' -RRB- claimed by people -LRB- increasing from an average of two or three to approximately 16 -RRB- .. identities. Identity ( social science ). DID is also controversial within the legal system , where it has been used as a rarely successful form of the insanity defense .. insanity defense. insanity defense. The 1990s showed a parallel increase in the number of court cases involving the diagnosis .. DID became a popular diagnosis in the 1970s , '80s , and '90s , but it is unclear whether the actual rate of the disorder increased , whether it was more recognized by health care providers , or whether sociocultural factors caused an increase in therapy-induced -LRB- iatrogenic -RRB- presentations .. iatrogenic. iatrogenic. The unusual number of diagnoses after 1980 , clustered around a small number of clinicians , and the suggestibility characteristic of those with DID , support the hypothesis that DID is therapist-induced .. hypothesis. hypothesis. The unusual clustering of diagnoses has also been explained as due to a lack of awareness and training among clinicians to recognize cases of DID .