![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
A deeper dive into the “Studies show that 1% of people have DID” claim
The bad news: if I had bet money on that plurality stat from the other day, it looks like I would’ve lost.
The good news: LB Lee came through with the citations, and between us I think we’ve nailed it down for real this time. Also, brought my list of relevant studies up to 5 — which is still tiny, but hey, still better than one.
So, consider the previous mini-vent a trailer for this full-length dissection.
The big one, probably the actual Ground Zero source for the statistic, from 1991:
- Ross, C. A. (1991). Epidemiology of multiple personality disorder and dissociation. Psychiatric Clinics of North America, 14(3), 503–517. 10.1016/S0193-953X(18)30286-7
The abstract flat-out says “multiple personality disorder related to childhood abuse affects about 1 % of the adult population.”
(MPD was renamed to DID in the fourth edition of the DSM, released in 1994. This research straddles the year of the name change, so you’ll see both terms come up.)
I don’t have access to the full text, but Ross discusses the study in the second edition of his book, Dissociative identity disorder : diagnosis, clinical features, and treatment of multiple personality (1997). Sample was 502 people in Winnipeg, screened with the Dissociative Experiences Scale, then later re-evaluated with the Dissociative Disorders Interview Schedule.
From the book:
There are a number of serious methodological limitations to the DDIS portion of this study: No validating clinical interviews were conducted; the validity of the DDIS in nonclinical populations is unknown; the sample size is too small; the data come from only one city; and no other standardized interview was administered. Because of these limitations, the data from the study, shown in Table 5.2, must be regarded only as first approximations. The 1% prevalence of DID is a conservative interpretation of the data, because over 3% of respondents endorsed DSM-III-R criteria for multiple personality disorder. I excluded most of these people as false positives because they reported neither trauma histories nor the rest of the DDIS symptom profile for DID. It is clear that the DID cases detected in this study are far milder in symptom severity than clinically diagnosed cases, including their DES scores.
Several other interpretations of the data are possible. First, the prevalence of severe DID may be less than 0.2% because no such cases were detected in a sample of 502 respondents. Second, these data provide the strongest existing scientifically based (as opposed to ideologically based) argument in favor of the iatrogenic amplification of DID. If cases existing in the general population are mild, and those diagnosed clinically are severe, it is possible that symptom levels get amplified during recruitment into the mental health system in a substantial proportion of cases.
Much more research and more advanced methodology are required before any firm conclusion can be reached about the epidemiology of DID in the general population. (109)
So! Bunch of thoughts here:
- Wow, that’s a lot more softpedaling and caveats than he presents in the study itself, huh
- Spoiler alert, the next few studies have the same “methodological limitations”
- The way 2% of this group managed to “endorse DSM-III-R criteria” for MPD without having trauma histories or severe dissociation…this 2014 literature review pins it on the early criteria not involving amnesia at all, which was added in later versions of the DSM
- Again, the DDIS is a screening tool, it doesn’t give you a diagnosis (which Ross would know, since…he developed it)
- Which means, again, the 1% number appears to be “people whose DDIS results say DID is a possibility to look into,” not “people who definitely have DID”
- This number comes with even more caveats, but: “less than 0.2%” is a possible, preliminary estimate for the general-population rate of “people who have clinically-diagnosable DID”
- It’s unnerving to see a doctor present “people who seek mental-health treatment have worse symptoms than people who don’t” as an argument for treatment making the symptoms worse
A lot here depends on what exactly Ross means by “symptom severity.” Is he saying his DID patients have more disruptive/debilitating symptoms, while the study is flagging people who might be plural systems, but more healthy and well-adjusted about it?
Or does he just mean symptoms that are farther outside the norm — say, the study is flagging systems who only report 2 alters, while his patients all have at least 20? Or what?
(average system has 0 alters, Headmates Georg is an outlier and should not have been counted–)
Two more studies by Ross’s students, 1991 and 1994:
- Ross, C. A., Ryan, L„ Voigt, H., & Edie, L. (1991). High and low dissociators in a college student population. Dissociation, 4, 147-151.
Sample of 345 college students in Winnipeg, 8 of them (about 2.3%) came up as “people whose DDIS results say DID is a possibility to look into.”
- Murphy, P. E. (1994). Dissociative experiences and dissociative disorders in a non-clinical university group. Dissociation, 7, 28-34.
Sample of 415 students at the University of Idaho, 4 of them (about 1%) came up as “people whose DDIS results say DID is a possibility to look into.”
The study I found earlier, from 2007:
- Sar V, Akyuz G, Dogan O, 2007. Prevalence of dissociative disorders among women in the general population. Psychiatry Res. 149, 169–176. 10.1016/j.psychres.2006.01.005
Sample of 628 women in Sivas, Turkey, 7 of them (1.1%) came up as “people whose DDIS results say DID is a possibility to look into.” (I found another study from 2014 by the same people, but it appears to be a different evaluation of the same sample group.)
Some digging turned up one more, from 2006:
- Johnson JG, Cohen P, Kasen S, Brook JS. Dissociative disorders among adults in the community, impaired functioning, and axis I and II comorbidity. J Psychiatr Res. (2006) 40:131–40. 10.1016/j.jpsychires.2005.03.003
Sample of 658 people in New York State. This is the only one that didn’t use the DDIS; apparently it used a bespoke combination of items from the DES and the Structured Clinical Interview for DSM-IV Dissociative Disorders. 1.5% came up as “people whose results on this custom setup say DID is a possibility to look into.”
I found that cited in Dissociative identity disorder: An empirical overview, a 2014 literature review. It was the only mention of a specific “trying to measure the rate in the general population” study that hadn’t already been scrounged up by either me or LB.
Looking at “related research” for any of these brings up a lot of studies about dissociative disorders overall, or dissociation in general as a symptom. So it’s possible some of those tried to get rates of DID along the way (and if it was since 2014, that one group of reviewers wouldn’t have found it). But I didn’t go paging through them to check.
That makes 5 studies, done in 3 countries, across 2 continents, being fairly consistent about “at least 1% of the general population has serious-enough dissociative symptoms to rate follow-up evaluation for DID.”
Obviously we should have more research. And I don’t know if this number would bear out under more studies. But you know, I wouldn’t be surprised or skeptical if it did? In my personal, non-medical, non-expert opinion, this sounds credible! The vibes check out.
And it’s still not the same as saying “1% of the general population has for-sure diagnosable DID.” There are, to date, zero (0) studies where the data support that.
(Sidenote: none of these studies have even looked for “people who have the experience of being plural, whether or not they qualify for a DID diagnosis.” So the prevalence of that could, conceivably, be higher. Based on vibes alone, I suspect it’s not a lot higher.)
A section I have to put in here somewhere:
Colin Ross is a Problem Guy.
That doesn’t mean he’s wrong 100% of the time — some patients have reported amazing and helpful therapeutic experiences with him. And of course, some critics want to discredit anyone who acknowledges DID at all. (Along with, you know, anything that involves confronting the long-term effects of serious child abuse.)
But other critics, including patients, accuse Ross of committing serious medical abuse. In a broad and depressingly-plausible range of ways — including plenty of things that would’ve been abusive from any doctor, with any patient, unrelated to whether they should have gotten an MPD/DID diagnosis or not.
This harrowing interview with an ex-patient, who ended up suing him for malpractice, starts with “he diagnosed me with MPD after 15 minutes of conversation” and vaults all the way to “he convinced me I had been abducted by aliens and gave birth to a half-alien baby.” It’s not good!
So maybe it’s not surprising that this particular guy massaged his “1% of the population” statistic until it said the more-dramatic thing he wanted it to say.
We know he did not invent DID, previously MPD, previously [doctor’s multi-paragraph explanation of how their patient has this strange dissociation-based experience of being more than one person in the same body]. Other medical professionals were already documenting that 40+ years before Ross was born.
But he did develop the DDIS! Which is used in 4 of these 5 studies! It’s widely used in good faith by doctors who I hope are mostly not-terrible, it does well when tested on patients with already-diagnosed dissociative disorders, and I haven’t seen any studies (or callout posts) that discredit it…but I wouldn’t blame anyone for worrying, just from the Colin Ross of it all.
And even if the DDIS is rock-solid, and hugely useful for the thing it was actually designed to do (help rule in/out possible diagnoses for a person who came in actively seeking mental-health support)…nobody has done a study big enough to say “of the 1% of average people this interview flags for DID follow-up, how many of those get the diagnosis when you do the follow-up?”
(Since it rules out 99% of people, if you want to end up with a sample of at least 100, you need to start by running the interview on a group of at least 10,000.)
The DID rate could turn out very close to 1% of the general population. It could also be 0.01%. We just don’t know.
So that’s the deal. If you’re reading this and you know of any relevant studies I missed (or if new ones have come out since I posted), drop a comment, I’ll add it to the list.
And if any DID Youtubers come across this post and want to use the history/research as a jumping-off point for a video…go for it. The platform could really use somebody to bring it up there.
no subject
no subject
Let me tell you, Erin, it was SURREAL being in the same room as Colin fuckin' Ross for a con in 2015. He was treated like a little tin god, and the whole time I'm just looking at him like :| and waiting for him to start talking about shooting forcebeams from his eyeballs and crap. One day, I'm probably going to have to do a deep-dive on him, but... ennnnnnggggggh it'll suuuuuuck, I don't wanna...
no subject
From the stuff of his I ended up reading while researching this post, he did a good job of coming off as thoughtful and measured when weird/paranormal/conspiracy stuff came up. There's a whole chapter in The Osiris Complex where he talks about using religious trappings when helping a group of headmates reach out to a "demon alter," not because he thought this was a literal demon, but because they were shaped by that cultural context and he was trying to meet the system where they were at. (And -- according to him -- it went well!)
There are definitely moments where I got a weird feeling...but nothing big enough that I could have guessed "this guy is also known for claiming he can shoot lasers from his eyes and telling his patients the CIA implanted them with alien babies."
Youtube has now put a couple of his presentations/lectures in my recommended videos, and I don't know if I want to watch any to see if that impression holds up, or if I should just not give him the views.
As a heads-up -- I ended up reading a bunch of the comments on that patient interview, and Ross himself shows up to write a lengthy rebuttal. (The OP's reply has a line that is also my reaction: "I find it unsatisfactory as a denial of the claims against you. It reads much more like a lawyer’s oration which seeks only to cast “reasonable doubt”.") So if you're looking for more reasons to avoid trying to do a writeup on him...there's one!
no subject
no subject
no subject
...On reflection, I've been using "DID Youtube" to mean something loose like "Youtubers who make videos where DID would be one of the SEO keywords," without trying to track what specific diagnoses anyone does or doesn't have. So, not ideal -- but I'm not sure there's any replacement term that would be, either.
no subject
crow&: also no worries, didnt think you were!! (frankly sometimes we forget anyone has watched any of our videos ever, so thanks! also i think we have been guilty of echoing that statistic, so, oops, and glad to correct it!)
no subject
no subject
no subject
Fascinating stuff!! Thanks for your hard work.
Here's something that's helpful for conceptualizing how much "1% of the population" really is: natural gingers are also just around 1% of the population!
no subject
I wasn't rude enough to reply with "maybe it's not actually that common" with zero evidence to back that up. But I did think it.
no subject
So, here’s the thing. I know a lot of multis. I think many people would agree that I know way more multis than the average person in America. I have also done a lot of reading about various forms of selvedness and spent a looooot of time thinking about it and kicking the tires.
And the 1% DID stat just kinda niggles at me! Because DID is just one form of many-selvedness, and though I don’t know for sure, I feel it describes a cultural phenomenon more than an objective cross-cultural medical condition. Like, tuberculosis is tuberculosis, be you in Canada or China. But what is considered madness or mental illness is EXTREMELY contextual. Falling on the floor howling gibberish at work would get you sanctioned; at certain churches, it would be normal. It troubles me, the idea of enforcing our idea of what DID is (and the idea that it’s the ONLY form of many-selvedness) as though our standards are objective and other cultures are not.
Also, just basic thought makes me go, if DID is 1%, and it’s just one kind of multi, then how many percent are the others? I should be tripping all over multis and while they are far more common than others think, I still don’t think there’s THAT many. By being a public figure who runs a meetup, I naturally meet way more than average!
The thing that really troubled me is, DID is considered a very white condition. Which makes no sense if DID is also supposed to be a trauma condition, especially SEXUAL trauma. We have a very prominent and infamously sexually traumatized demographic; to be blunt, where are/were all the black multis in slavery times? Either our records (and thus prediction of DID prevalence) are massively lacking, or something’s wrong with how we conceptualize DID (which also renders all stats about its prevalence suspect).
I get that people want to prove that we’re more common than presumed, with the idea that if it’s common, it must really exist. But that ain’t necessarily so.
Tldr, the statistic never felt that helpful to me, and Colin Ross is a creep and I pettily dislike and distrust him so don’t trust a word he says.
no subject
Your impression of "I don't think there's that many" holds a lot of weight for me, because nobody could dismiss it with "oh, you've probably met more than you know about, because you're not looking for/not believing in them."
...I actually think the statistic is a little more reliable than what you're describing here, because it's not based on "what records can we find" or "who have we already diagnosed".
We know there's plenty of studies to show biases like "when a black person and a white person report the same pain levels, doctors tend to give the white person better pain medication." Seems reasonable to infer that, if a black system and a white system report the same symptoms, the white patient is more likely to get "let's screen you for DID" and the black patient is more likely to get "let's put you on antipsychotics/that's not a big deal, suck it up/you're probably lying to get drugs, go away."
On the other hand, these studies are all "we got a sample of hundreds of people, and no matter what demographics they fell into, we ran them through the same standardized interview, and compared the results." That avoids some of the pitfalls of "we got a sample of people who actively looked for mental-health treatment, which is skewed by the fact that some groups get worse treatment in the medical system, and we only ran them through the interview if the treating doctor thought about it, which is skewed by the doctor's biases."
Also -- knowing that the 1% statistic isn't as specific as "people who have been full-on diagnosed with DID" means I wouldn't be surprised if it did catch other forms of many-selvedness. (The 2014 study by Sar et al, the second one on the women in Turkey, also analyzed their self-reported experiences of possession!)
I can imagine a world where more doctors in more countries ran different groups of people through the DDIS, and it always flagged around 1% of them, even if those 1% went on to be categorized/defined in different ways based on local cultural expectations. I wouldn't assume the interview is that neutral -- would be a huge leap to go there without doing the studies first -- but it doesn't seem outside the realm of possibility, you know?
The idea of "[systems] want to prove that we’re more common than presumed, with the idea that if it’s common, it must really exist" has been my impression too.
And yeah, it doesn't invalidate a thing if we discover/acknowledge that it's rare! To borrow a comparison that gets used a lot with nonbinary genders...the proportion of atoms in the universe that are, say, copper is only 0.000006%. Somehow, we can all still accept that copper exists.
no subject
PENNIES ARE COOKED UP BY TRADFI!