In our Dissociation Resource Guide [and on our website here and here] we provide a table of statistics detailing the prevalence rates for dissociative identity disorder and other dissociative disorders based on a number of studies conducted across the world. Statistics like these are not merely academic. They tap into fundamental questions that haunt many of us survivors: Am I the only one? Am I all alone? Many therapists ask the questions: is dissociative identity disorder rare, and is it therefore something I am unlikely to come across in my professional career? Because if it is rare, perhaps I don’t need to know about it, and certainly I don’t need to spend time and money on training for it. Or if I do happen to come across dissociative identity disorder, is it so specialist (another word, really, for rare) that I should immediately refer it on? Or is it, as the ISSTD (International Society for the Study of Trauma and Dissociation) believe, ‘relatively common’ (2011, p.118)?
dissociative identity disorder - Common or Rare?
As a survivor with dissociative identity disorder, it makes a big difference to me whether it is common or rare. Are there other people like me? Are there enough people with dissociative identity disorder in this country for it to warrant research and NICE treatment guidelines? Or am I all alone in this, unlikely to meet anyone else who can empathise with my experience? Is it just me? Some people might relish the thought of being that unique or ‘special’, but personally I would prefer to feel less alone. I don’t want to be ‘rare’. I don’t want to be sensationalised. I don’t want a therapist, or anyone else for that matter, to recoil with shock at meeting someone with dissociative identity disorder as if an almost-
My experience, of course, through PODS’ training days and similar events, is that I now know an awful lot of people with dissociative identity disorder and I have a significant group of people I would classify as ‘friends’ who all have it too. Anecdotally it doesn’t seem rare to me at all. But what does the research say?
The research, I have to admit, is a bit ambiguous. The ISSTD in their updated Treatment Guidelines (2011) place the prevalence of dissociative identity disorder at about 1-
Understanding statistics is hard enough as it is, without the facts being buried in obscure research papers. Newspapers are forever quoting seemingly-
So where do the figures pertaining to the prevalence of dissociative identity disorder and dissociative disorders actually come from, and why do they differ so wildly? The first thing to take into account is whether the study is based on inpatients, outpatients or people in the general community. This can made a big difference: you would expect to see a higher rate of mental health disorders on an inpatient unit than you would in the general population, despite that other joke about how people who work on mental health units are more mad than their patients…
Analysis of Prevalence Studies
A review of prevalence studies shows that dissociative identity disorder is found in 0.4% to 7.5% of psychiatric inpatients (Sar, 2011). Rates for outpatients—people accessing mental health services but on an appointment basis—range from 2% to 6%. And finally, community studies—research based on people with no involvement with mental health services, i.e. ‘Joe Bloggs’—show the prevalence of dissociative identity disorder ranging between 0.4% and 3.1%. That would equate to quite a large number: between about 250,000 to just under 2 million people in the UK. To put that in perspective, prevalence rates for schizophrenia generally sit around the 0.55-
But dissociative identity disorder is only the top end of the spectrum. When researchers look at the whole range of dissociative disorders, prevalence varies between 4.3% and 40.8% in inpatient samples (Sar, 2011), 12% to 38% for outpatient samples (Brand et al, 2009a) and 1.7% to 18.3% for community samples (Sar, 2011). So, in theory, between roughly 1 million and 11 million people in the general UK population suffer from a dissociative disorder of some description. That is an awful lot of people, and it’s a huge variation.
In order to make sense of such differing rates, it is vital to consider what it is that prevalence studies are looking for. There has to be a definition of the disorder that they are seeking to study. So how do you define dissociative identity disorder, and how do you define dissociative disorders? Do you take the diagnostic criteria of the DSM-
- The presence of two or more distinct personality states, each with its own relatively enduring pattern of perceiving, relating to, and thinking about the environment and self
- At least two of these identities or personality states recurrently take control of the person’s behaviour
- Inability to recall important personal information that is too extensive to be explained by ordinary forgetfulness
- The disturbance is not due to the direct physical effects of a substance (eg blackouts or chaotic behaviour during alcohol intoxication) or a general medical condition (eg complex partial seizures) (APA, 2000).
Or do you take a different definition, for example the European classification system, the ICD-
Then there are cultural issues for research samples. As the ISSTD (2011) points out, contrary to accusations from people in the ‘DID-
Finally there are also what are known as ‘methodological’ issues in research studies, which affect how reliably and seriously the data can be taken—variables such as how many people took part in the study and whether data was gathered by self-
The Misdiagnosis of dissociative identity disorder
Despite these issues, what many of the prevalence studies on dissociative identity disorder and dissociative disorders point to or at least hint at is the fact that it often goes undiagnosed or misdiagnosed. In one study by Foote et al (2006), 29% of his sample had a dissociative disorder and yet only 5% had been previously diagnosed. Sar et al (2000) also saw this in Turkey where 12% of outpatients qualified for a diagnosis of a dissociative disorder and yet only 1% had received one. (Presumably, when researchers come and do these studies, the people with the budgets to treat people afterwards aren’t always jumping for joy.) The ISSTD (2011) suggest that someone can spend between 5 and 12 years in the mental health system before receiving a correct diagnosis, and Brand et al (2009b) suggest that on average people receive 3-
It is well documented that dissociative identity disorder is often misdiagnosed as borderline personality disorder, psychosis, schizophrenia or bipolar affective disorder, amongst others. There is also a question in many people’s minds about whether these are just straightforward misdiagnoses or whether they are ‘co-
All of this brings into focus the whole concept of what a diagnosis is anyway, and whether the criteria for one particular label are ‘right’ and whether there can be any overlap between different conditions. Or is it in fact that these disorders exist on a spectrum and it’s more a case of a ‘buffet lunch’ of symptoms rather than a ‘set menu’?
For instance, many of the defining aspects of dissociative identity disorder from a phenomenological model (looking at the patient’s actual experience) include symptoms such as self-
This is why a bit of a debate raged amongst clinicians and researchers about whether the DSM-
The criteria update in 2013 for DSM-
Dell (2006) has proposed a different model of dissociative identity disorder which is based on a range of symptoms, rather than the exclusive emphasis on ‘two or more identities’. He argues that the DSM ‘description of dissociative identity disorder is deficient because it omits most of the dissociative phenomena of DID and focuses solely on alter personalities’ (Dell, 2006, p.1). He believes that a much broader range of elements should be taken into consideration in diagnosing it, such as flashbacks, somatoform symptoms, and ‘partial intrusions’ from others parts of the self, for example hearing voices, or ‘made thoughts’ or temporary loss or gain of a skill or knowledge.
Of course one of the problems with dissociative identity disorder is that we struggle enormously with shame and we don’t want to be noticed, diagnosed and measured. On top of this, many of us struggle for years with bizarre behaviours and symptoms which we do our best to hide from the world and so we have no idea at all that we suffer from a ‘condition’ at all. Usually it is only when things get bad enough for us to suffer a breakdown or other circumstances conspire for us to need to seek help, either medically or in the form of counselling, that we begin to admit—not just to others but also to ourselves—that we may have ‘problematic’ behaviours and a ‘disorder’.
The focus on ‘two or more identities’ can mean, as the research has said, that it takes us many years to get an appropriate diagnosis. But more accurate diagnostic criteria that take into account our actual experience of living with dissociative identity disorder rather than a hangover from Sybil would of course again change the way that prevalence rates of dissociative identity disorder and dissociative disorders are measured.
How prevalent really is dissociative identity disorder?
I believe that prevalence rates for dissociative disorders are hugely under-
Essentially I want to be heard, shown compassion and empathy, and to be seen as human, as me. Mostly as dissociative survivors we want therapists and counsellors just to get on and work with us as we are in the therapy room, and labels can sometimes get in the way of that. But the encouraging thing is that dissociative identity disorder actually has a very good prognosis if treated appropriately (Brand et al, 2009a).
So I am not the only one. I am not alone. I am not rare. Not a Javan Rhino…but as common in the UK in fact as the hedgehog. So yes, therapists, you are likely to come across dissociative disorders and dissociative identity disorder in your everyday practice. In fact, understanding of dissociative disorders is essential for everyone. As Vedat Sar (2011, p.6), a leading researcher in this field, says:
… due to their link to early-
(Sar et al, 2011, p.6)
© PODS 2011