premise: Multiple personality disorder is another name for Dissociative identity disorder.
hypothesis: Dissociative identity disorder ( DID ) , also known as multiple personality disorder ( MPD ) , is a mental disorder characterized by at least two distinct and relatively enduring identities or dissociated personality states . In psychology and mental health , the host is the most prominent personality , state , or identity in someone who has Dissociative Identity Disorder ( DID ) ( formerly known as multiple personality disorder ) .