When it comes to diagnosing Dissociative Identity Disorder, there are three mistaken beliefs that are common and can lead to a clinician failing to correctly diagnose DID.
Myth #1: Switching
It is not necessary for the clinician making the diagnosis to witness the person switch. It is not necessary for anyone to see the person switch. It is sufficient for the person being evaluated to report that it is happening.
Myth #2: Internal Communication
Internal communication is not a requirement for a diagnosis of DID. It is not necessary that the person is able to communicate with insiders. Nor is it necessary for the person to even hear insiders talking to them or to each other.
Myth #3: External Communication
The therapist does not need to communicate directly with any alters in order to make a diagnosis of DID.
And a Bonus Mistaken Belief
And this is one that I haven’t seen any clinicians say, but I’ve seen plenty of people in general say: that you can’t have DID if you are aware of alters. This is also incorrect. So if you are aware of alters but have believed that meant you couldn’t have DID, well, you may want to talk to a mental health professional who is knowledgeable about DID.