There was a discussion on a DID forum I participate on, in which someone asserted that there is a hierarchy of trauma-based disorders from PTSD via chronic PTSD and other dissociative disorders to dissociative identity disorder. I have read similar things before, such as in the dissociative spectrum, where depersonalization is on one end and DID is on the other, with dissociative amnesia and dissociative disorder not otherwise specified being inbetween.
I strongly disagree with this hierarchy of disorders. After all, both depersonalization disorder and PTSD – the “mildest” forms according to either spectrum – can be very severe and disabling. It is true that depersonalization and other dissociative phenomena often accompany DID, so in that respect the dissociative spectrum makes some sense. However, it is not always true that DID encompasses all other dissociative phenomena.
Secondly, there is a lot of overlap between dissociative disorders and (chronic/complex) PTSD. There is also a lot of comorbidity. This makes it harder to presume a hierarchy between PTSD and DID: most people with complex or chronic PTSD, also have some dissociative features or disorder, and most people with DID or DDNOS also have a form of PTSD.
Lastly, it is simply invalidating to presume a hierarchy of trauma-based disorders. No trauma is “mild”, and its consequences should never be trivialized. Presuming a continuum of trauma or its consequences, is therefore offensive to people presumed to be “mildly” affected.