There exist mutliple models of DID They mostly focus on how it is caused There is a distinct lack of description what it is like The socio-cognitive model still does not poes any evidence despite its long history There is some bio-neurological evidence supporting the structural dissociation theory There are measurable differences between ANPs and NP when confronted to trauma memory which cannot be replicated within the control group The seem differences in the brain structure of DID patients The research is heavily focused on Trauma The problem with strutural dissociation is van der Hart has had his practioners license revoked due to a decade long abuse of his patients There does not seem a critical reevaluation of his theories taking this into account The descriped concepts in the theory are rarely to be observed so clearly in the open to the point of questioning how valid they are [citation needed]