the silliest of geese

According to the Diagnostic and Statistical Manual of Mental Illness (DSM-5), a history of childhood abuse and neglect is prevalent in 90% of cases of dissociative identity disorder (DID). The remaining cases involve medical trauma, terrorism, and childhood prostitution. Ninety percent is overwhelming. Other research claims that rates of abuse and neglect in DID are actually much higher.

DID develops in response to severe, recurring trauma in childhood. Children are not fully equipped to cope with continued, severe instances of abuse, so they may develop dissociation as a survival skill, which can then develop into DID. It makes sense, then, that the rate of childhood abuse and neglect in people with DID is so high.

https://www.healthyplace.com/blogs/dissociativeliving/2016/04/the-undeniable-connection-between-did-and-child-abuse

The authors interviewed 102 individuals with clinical diagnoses of multiple personality disorder at four centres using the Dissociative Disorders Interview Schedule. The patients reported high rates of childhood trauma: 90.2% had been sexually abused, 82.4% physically abused, and 95.1% subjected to one or both forms of child abuse. Over 50% of subjects reported initial physical and sexual abuse before age five. The average duration of both types of abuse was ten years, and numerous different perpetrators were identified. Subjects were equally likely to be physically abused by their mothers or fathers. Sexual abusers were more often male than female, but a substantial amount of sexual abuse was perpetrated by mothers, female relatives, and other females. Multiple personality disorder appears to be a response to chronic trauma originating during a vulnerable period in childhood.

https://pubmed.ncbi.nlm.nih.gov/2044042/

Causes

The main cause of DID is believed to be severe and prolonged trauma experienced during childhood, including emotional, physical or sexual abuse.

The development of dissociative identity disorder is understood to be a result of several factors:

Recurrent episodes of severe physical, emotional or sexual abuse in childhood.

Absence of safe and nurturing resources to overwhelming abuse or trauma.

Ability to dissociate easily.

Development of a coping style that helped during distress and the use of splitting as a survival skill.

While abuse is frequently present, it cannot be assumed that family members were involved in the abuse.

Dissociative identity disorder (DID) is the result of repeated or long-term childhood trauma, most frequently child abuse or neglect, that is often combined with disorganized attachment or other attachment disturbances. DID cannot form after ages 6-9 because individuals older than these ages have an integrated self identity and history. Trauma later in life can lead to posttraumatic stress disorder or complex posttraumatic stress disorder, other dissociative disorders including other specified dissociative disorder, somatic symptom disorders, or possibly borderline personality disorder, but DID requires an unintegrated mind to form.

https://did-research.org/origin/

Other helpful links!!

DSM-5 on DID and

A explanation of each DD

NAMIs fact sheet on DID

Please see this account for OP

A PDF research paper done on the link between DID and childhood abuse

My own multi-part research thread