Research Recap with Skye: Current Methods and Issues Surrounding ADHD
Welcome to Hacking Your ADHD. I'm your host, William Curb, and I have ADHD. On this podcast, I dig into the tools, tactics, and best practices to help you work with your ADHD brain. Today, I'm joined by Skye Waterson for our Research Recap series. In this series, we take a look at a single research paper and dive into what the paper says, how it was conducted, and try and find any practical takeaways.
In this episode, we're going to be discussing a paper called Evaluating Attention Deficit and Hyperactivity Disorder, ADHD: A Review of Current Methods and Issues. And this paper is a narrative review that surveys the current landscape of ADHD diagnosis, where the DSM criteria came from, how they've evolved, and any known problem areas that are in there.
If you'd life to follow along on the show notes page you can find that at HackingYourADHD.com/313
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William Curb: Welcome to Hacking Your ADHD. I'm your host, William Curb, and I have ADHD. On this podcast, I dig into the tools, tactics, and best practices to help you work with your ADHD brain. Today, I'm joined by Skye Waterson for our Research Recap series. In this series, we take a look at a single research paper and dive into what the paper says, how it was conducted, and try to find any practical takeaways.
In this episode, we're going to be discussing a paper called Evaluating Attention Deficit and Hyperactivity Disorder, ADHD: A Review of Current Methods and Issues. This paper is a narrative review that surveys the current landscape of ADHD diagnosis: where the DSM criteria came from, how they've evolved, and any known problem areas in there.
The paper covers a lot of ground in a relatively compact form, although it is about 21 pages. But it's quite a bit of fun to read. As I was going through it, I was thinking, "Actually, this is just well-written. I'm enjoying this," which was not quite what I was expecting. But, you know, let's get into it.
Skye Waterson: Yeah, I was saying before we jumped on the call that when I gave you this paper, I was expecting you to start by saying, "Skye, 21 pages? Seriously? I can't believe you made me do this." But it is—it's so good. It just had to be done.
This paper goes over the clinical presentation of ADHD, then it goes into the DSM throughout the years before talking about the DSM-5. Then we talk about diagnosing children, diagnosing adults, and evaluation tools in general. I would go as far as to say that if somebody said to you, "I want one paper that just really clearly explains what ADHD is. I've just been diagnosed, I know nothing about it," or maybe, "I want to know more about it before my first assessment," this is the paper I would probably recommend.
William Curb: Yeah, it's really good. And I do think we should mention, to make sure there's clarity on the distinction, that this is—as we said in the beginning—a narrative review. Typically on the show, we do more systematic reviews. A narrative review is where the author is picking and choosing content on what to include in the paper, rather than having a documented, reproducible protocol on how they looked up all the data.
So there can be some introduction of bias, but I really feel that with this paper, they do such a good job of breaking down every point they go through. They cover everything, so I understand why they did not do a systematic review for this kind of paper.
Skye Waterson: Okay, so let's jump into the first section. It's broken into different sections, and the first section is the background and prevalence of ADHD. They talk about this idea that it's one of the most common neurodevelopmental disorders, and we'll talk shortly about the shift in how the DSM grouped ADHD.
It affects 5.9% of children and adolescents, and 3.10% among adults, with inattentive as the most common type. Now, this was interesting to me because that number was lower than I had seen elsewhere, although I will say that when they talk about worldwide symptomatic ADHD for adults, that is more in line with the number I expected.
William Curb: Yeah, which is an interesting thing to try and actually wrap your brain around with numbers. Really, what this paper is going to be looked at for by a lot of people is: Is ADHD over-diagnosed? If we look at diagnosis rates around the world, we get an interesting situation. There are places where it could possibly be over-diagnosed, and other places where they don't even acknowledge that ADHD could be a thing.
Skye Waterson: I also think it's interesting that they say the worldwide prevalence for persistent ADHD is 2.5%, while symptomatic adult ADHD is 6.7%. It reminds me of the fact that a lot of the research we read is actually looking at symptomatic ADHD based on assessment, rather than diagnosed ADHD. In adults, it's almost more common now in the research that we're starting to have those two different conversations, and it kind of comes through here a little bit.
William Curb: Yeah. I mean, the number of people that I've talked to, like for my podcast or just in general, who say, "I have ADHD, I just haven't gone through the diagnostic process," is a lot of people. Especially for people who are not in the United States, where there is some barrier to getting a diagnosis, or places where they say, "Yeah, there's just no chance I would ever get a diagnosis in a reasonable amount of time."
Skye Waterson: A nine-month waiting list—yeah, exactly. I find the same thing in my work as well. A lot of business owners say, "Oh yeah, but I'm not going to get diagnosed. You know, I'm older, I've decided not to have that as part of it." So it does leave room for that.
When talking about clinical presentation, they do go into: Okay, well, what is ADHD? They reference the unifying theory established by Barkley in 1997, where executive dysfunction in ADHD is evident across four domains: behavioral inhibition, working memory, internalized speech, and the regulation of emotions, motivation, and arousal. That's kind of the "Barkley Four."
William Curb: Yeah. I really like Barkley's idea that a lot of it comes down to self-regulation. It makes so much sense to me to look at ADHD as a failure of self-regulation that affects all these areas. If I can improve self-regulation, that will improve all of the other domains.
Skye Waterson: Yeah, I really like it as well. I will say I feel like time blindness doesn't get as much of a showing in there as I would like it to, based on the research and the work I've done. When I work with clients, time blindness and working memory sit almost side-by-side in how much struggle they create. But outside of that, I think it's great.
William Curb: Yeah. And I could see an argument that self-regulation in time blindness is the inability to regulate that part of your brain to keep time in mind while trying to do tasks. But that's semantics at best.
Skye Waterson: Yeah, exactly. Which is kind of funny, because that is kind of what this paper is about—semantics. But yeah, then they talk about Mahone and their debate on early neuropsychological theories of ADHD, their considerations on disturbances in executive functioning, and they go through all the different areas of clinical presentation.
William Curb: Let's get into the DSM then, because this is the bit that I was really excited about. This is the main reason we pulled this paper—we wanted something that would give us a full history of the DSM. For those who may not have been diagnosed, this is the tool people use to diagnose ADHD.
It's really important to remember when talking about the DSM that it is primarily a tool for insurance. If you want something covered, what is being covered needs to be measurable. That is how the DSM was developed, but it is also used way beyond that scope for diagnostic work.
Skye Waterson: Yeah, and that's why it can sometimes feel very different from some of the more clinical conversations. The diagnostic value of ADHD first took place in 1968, but it was just called "hyperkinetic reaction of childhood" in the DSM-II. It wasn't really identified as ADHD until the 1980s.
William Curb: Yeah, and it even came in originally as ADD, and then expanded into ADHD—which is still something I get questions about.
Skye Waterson: Mm-hmm. Yeah.
William Curb: I don't think this paper specifically talked about that hiccup, but the idea of ADD entered into public consciousness, and it was only in the DSM for three or four years before it was updated to ADHD.
Skye Waterson: I think because it was the first name, I still get clients who say, "I have ADD," or "Everyone has ADD." That just tells me when you were diagnosed—it gives me that kind of context. But the DSM likes to change the labeling of things a lot, so I'm sure the next version will give us a totally different name or a totally different subgrouping. I try not to let that get in the way of what we're actually discussing.
William Curb: Yeah, because is it really that important for us to differentiate between ADHD subtypes versus ADHD presentations, even though they cover the same thing? It's just that they wanted to update the language to show that it can change over time. That makes sense, but I understand why people don't keep up with it. You shouldn't expect everyone to keep up with it.
Skye Waterson: Yes, 100%. That leads us to the latest version, which is the DSM-5, where they talk about ADHD Type 1 and Type 2: primarily inattentive, primarily hyperactive, and then the combined type. I know this almost off by heart now because I get asked about it on every single podcast I go on—what it is and what those differences are.
It is worth mentioning that in the DSM-5, ADHD became recognized as a neurodevelopmental condition rather than a disruptive behavioral disorder, which is a really big shift.
William Curb: Yeah, which is incredibly important for people being diagnosed—focusing on how it affects them versus how it affects other people, because that is often how the condition was historically presented.
Skye Waterson: Yeah. Historically, that was how it was identified. If you think about it, "hyperkinetic reaction of childhood" was the first version of this, and now we have it as a neurodevelopmental disorder. There is a huge shift in how we have come to think about ADHD throughout that journey.
William Curb: Yeah. And that changes how people self-actualize what having ADHD means for them as well.
Skye Waterson: Yeah, I agree. I'm very happy to be in the zone of this current version; I think it's getting better in that way. Then they talk about the criteria. For ADHD in the previous DSM, you had to have six symptoms, and in the DSM-5, that was reduced to five for adults. They discussed the pros and cons of that adjustment.
William Curb: Yeah. The other important part there was including adults as individuals who could be diagnosed.
Skye Waterson: Of course, yes.
William Curb: It seems so obvious that we need to be able to diagnose adults, but it was largely considered a childhood disorder. When reading older literature, they will talk about how it does not go away in adulthood, but then say, "But it is primarily a condition of childhood." It doesn't make sense.
Skye Waterson: Yeah. It even comes up here that the debate over whether ADHD is early-onset or late-onset is still ongoing. They went into some of the discussions about ADHD in adulthood: why it exists, the trauma conversation versus the "we just didn't notice" conversation.
William Curb: Yeah. So there is a lot in how the diagnostic criteria have changed, and I personally prefer a more inclusive approach. I applaud them for enabling this, because people aren't seeking out an ADHD diagnosis for no reason at all—it's usually because they're struggling. The only important thing, which we'll get into in a minute, is how it's being assessed, because you want to make sure you're giving the right diagnosis.
Skye Waterson: Yeah, exactly. It's a case of asking: Where do you fit in this space? This happens to people on both sides of the spectrum. Some people come in for anxiety, and the clinician says, "Actually, if you get ADHD support, this is going to be greatly helped, so let me not give you an anxiety diagnosis right now—that wouldn't be as helpful." Other people come in with suspected ADHD and they say, "Oh, this is probably depression or something in that realm, or maybe a combination." So it's really about which diagnostic profile is going to help you with the struggles you're having.
William Curb: Yeah, and that's exactly where this paper goes. It talks about every evaluation tool—every single one. It's very comprehensive. But it starts off with the gold standard: the clinical interview. I didn't realize that the Schedule for Affective Disorders and Schizophrenia for School-Age Children / Diagnostic Interview Schedule for Children (DISC-5) is a structured, interview-based screening tool that involves six modules and approximately 3,000 questions.
Just as a caveat, they do not ask you all 3,000 questions! But about 350 of them are categorized as stem questions given to all respondents, meaning this kind of clinical interview is very comprehensive.
Skye Waterson: Yeah. You get the feeling reading this article that they have childhood diagnostics for ADHD pretty dialed in at this point.
William Curb: Yeah. Especially because you want teacher reports, parent reports, and clinic reports to see how people react in different settings. That might be a bigger indication of what's going on rather than strictly an ADHD diagnosis. If they are only acting out at school or only acting out at home, that tells you a lot about what's going on.
Skye Waterson: Yeah, definitely. It raised a few questions for me. This is the gold standard, and it seems very good. If your child goes through this diagnostic process and comes out with an ADHD diagnosis, you can be pretty confident that's what they've got.
But one of the controversies is: How consistently is this particular process actually being used across different areas in day-to-day life?
William Curb: Yeah, that's the big thing. I've talked to people who said, "Yeah, I walked into the doctor's office and said I had ADHD," and the doctor said, "Yeah, I think you do," and that was the entirety of their diagnostic process. That's not good enough—that's a problem.
Skye Waterson: Yeah, 100%. Do they discount certain reports? Do they look at teachers? Do they look at formal assessments? This paper breaks it down really well, but I couldn't help thinking I wished they had a section on practical implementation and use—a chapter on how much clinicians are actually using these tools for real-world assessments.
William Curb: Yeah. They did discuss systemic problems in the criteria as well. Questionnaires were historically developed using predominantly male children as samples. That provides some of the reasons we are seeing big changes in the criteria now, because we're discovering that women also have ADHD.
Skye Waterson: Yeah, exactly. Women also have ADHD, and adults also have ADHD. We're still not sure why—maybe you were loved too much or not enough, as the joke goes!
It feels like this is a great paper for describing the gold standard, but it gave me a level of expectation about diagnostic quality that I know from experience isn't happening everywhere. That was one of the bigger takeaways for me.
William Curb: Yeah, and it's also not clear how we're going to get there, partially because going through that full gold-standard process is expensive, and not everybody is going to be able to afford that.
Skye Waterson: Exactly, and that's a really good point. It's already very expensive. In New Zealand, they recently made some adjustments to make it less expensive because of how difficult it was and how many people wanted to get diagnosed.
That also makes sense when people ask, "Is there an ADHD pandemic? It's everywhere!" But when you look at it, we only realized it was really a thing in the '80s. The '80s isn't even vintage yet! It's still in that space where, for me, I think, "That's just my parents' generation." Of all the conditions in the DSM—depression, anxiety, and so on—those have much longer recorded histories than ADHD. It makes sense that people are starting to find out they have it simply because of how recently we identified it.
William Curb: Yeah, that's roughly 40-something years of its existence. This reminds me of a factoid I heard a while ago: the first person to ever be diagnosed with autism died only recently.
Skye Waterson: Wow.
William Curb: That is how recent it is! You'd think that would have happened 100 years ago.
Skye Waterson: Yeah! I don't know if we have data on the first person to be diagnosed with ADHD, but based on statistics, it's very likely they're probably still alive.
William Curb: Yeah. If someone wasn't diagnosed until the '80s and it was considered a childhood condition, then yeah, they're probably still with us.
Skye Waterson: We're going to wrap things up here because this is a 21-page paper, and there is so much more to talk about in it.
William Curb: And we will come back to you with Part Two in a few weeks.
Skye Waterson: Looking forward to it!