Right now, the actual number of people who are living with dissociative identity disorder is unclear, due in part to the fact that DID often goes undiagnosed or is misdiagnosed. Dr. David Spiegel, MD of the Stanford University School of Medicine, reports that one small study of DID estimates that approximately 1.5 percent of the adult population has the disorder at any given time, although other sources indicate the prevalence of DID is much lower.
Interestingly enough, a study of adults in a drug and alcohol treatment program conducted by Debra Benishek, MSN, RNC, FNP, and Dr. Harriety Conley Wichowski discovered a strong link between substance abuse and dissociative symptoms that are common among people with DID. The researchers found that one-quarter of the 51 subjects they surveyed scored high enough on a self-reporting tool to qualify for a diagnosis of DID. These results, along with literature reviews that achieved similar outcomes, led the researchers to conclude that “dissociative experiences are common among people who abuse substances” and that “routine screening for dissociative disorders should be considered for people who are chemically dependent.”