Dissociation and PTSD
Dissociation and PTSD are strongly related disorders resulting from trauma. They are often diagnosed together.
It would be highly unlikely to have a diagnosis of Dissociative Identity Disorder (DID) or OSDD without having a PTSD diagnosis.
Dissociative symptoms and experiences are very common in individuals who suffer from PTSD. They may experience more or less symptoms of depersonalization or derealization, and may have a tendency to dissociate when stressed and/or not remember aspects of their trauma because it’s hidden behind a dissociative barrier.
If there are a lot of experiences of derealization or depersonalization we may diagnose someone as having a dissociative subtype of PTSD.