Written by Bethany Blankenhiem, LPC, ADHD-CCSP, CACII | Licensed Professional Counselor & Certified ADHD Clinical Services Provider at InDepth Therapy

This article is for informational purposes only and does not constitute medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional about your specific situation.

Key Takeaways

• Adult ADHD is widely underdiagnosed: fewer than 20% of adults with ADHD have received a formal diagnosis or are currently being treated, according to estimates cited by ADDitude Magazine.
• Checklists and self-report scales have a critical limitation: research shows their positive predictive value can fall below 20% in clinical populations — meaning most positive screens are false positives, often driven by anxiety or depression mimicking ADHD.
• Symptom overlap is the core problem: up to 75% of adults with ADHD have at least one other psychiatric diagnosis, and conditions like anxiety, depression, and bipolar disorder share enough surface symptoms to consistently fool questionnaire-based screening.
• Neuropsychological testing adds objective data that self-report cannot — measuring how the brain actually performs attention and inhibitory control tasks, not how a person remembers or perceives their own functioning.
• The T.O.V.A. is an FDA-cleared neuro-performance test that provides quantified, normative data on attention variables — a key tool for differentiating ADHD from conditions that look like it.
• A comprehensive evaluation combines both: neuropsychological testing, clinical interview, history, and collateral information — no single tool diagnoses ADHD alone.
• InDepth Therapy offers T.O.V.A. testing in Broomfield and Fort Collins, CO as part of a comprehensive clinical evaluation led by a certified ADHD specialist.

You’ve spent years being told you’re disorganized. Unmotivated. Too anxious. Maybe even a little depressed. You’ve tried medication for one thing, then another. Some helped a little. Nothing has helped enough.

Then one day — maybe after a partner’s diagnosis, or a thread you fell down at midnight — it clicks: what if it’s been ADHD this whole time?

You’re not alone in asking that question. A 2024 survey by Ohio State University’s Wexner Medical Center found that 1 in 4 adults suspects they have undiagnosed ADHD. And the clinical data backs up the concern: according to the CDC’s 2023 analysis, roughly 15.5 million U.S. adults have a current ADHD diagnosis — and more than half of them were first diagnosed in adulthood.

But here’s the problem that too few people talk about: the way most adults get screened for ADHD — a checklist, a questionnaire, maybe a 15-minute appointment — is often not enough to tell the difference between ADHD and the constellation of other conditions that share its face.

This article explains why that gap exists, what neuropsychological testing adds to the picture, and how a more rigorous evaluation — including an FDA-cleared attention performance test — gives you answers that a symptom checklist simply cannot.

Why Adult ADHD Is So Hard to Diagnose

ADHD has historically been understood as a childhood condition — a rambunctious boy who can’t sit still. But the clinical reality is far more complex and far less visible in adults.

According to a 2024National Academies of Sciences workshop report on adult ADHD, ADHD in adults typically presents not as hyperactivity but as executive dysfunction — difficulty juggling competing demands, chronic procrastination, impulsivity in relationships or finances, and an inability to start or sustain tasks that aren’t intrinsically motivating. These are quieter symptoms, easily mistaken for personality traits or attributed to stress, burnout, or other diagnoses.

Adding to the complexity: adults bring decades of accumulated experience, injuries, anxieties, and adaptive behaviors that can mask or mimic ADHD. The same National Academies report notes that 20–30% of all adults report elevated ADHD-like symptoms on screening tests at some point in their lives — and nearly 90% of those are false positives.

This isn’t a failure of awareness. It’s a fundamental diagnostic challenge. And it’s why the tool used to evaluate adult ADHD matters enormously.

The Checklist Problem: What Self-Report Screening Misses

When most adults seek an ADHD evaluation, they’re handed a rating scale — typically the WHO’s Adult ADHD Self-Report Scale (ASRS) or a similar questionnaire. These tools are genuinely useful for one thing: ruling ADHD out. Their negative predictive value exceeds 96%, meaning a negative screen is reliably reassuring.

The problem is the other direction. A systematic review published in Psychological Assessment examined 20 studies of adult ADHD screening tools and found that while these scales reliably exclude ADHD, positive predictive values in clinical populations reached only 61% at best — and most fell below 20%. In plain terms: the majority of adults who screen “positive” on a symptom checklist do not actually have ADHD.

A separate PMC study on self-report ASRS screening found that in two independent population samples, the WHO’s most widely used ADHD screener flagged probable ADHD in 17–26% of participants — against an expected true prevalence of about 2.5%. The estimated positive predictive value: just 11.5%.

Why is the false positive rate so high? Because the symptoms of ADHD — poor concentration, restlessness, impulsivity, emotional dysregulation — are also cardinal features of anxiety, depression, bipolar disorder, trauma responses, sleep disorders, and chronic stress. Research published in BJPsych Advances found that 75% of adults with ADHD have at least one other psychiatric diagnosis — and often it is the co-occurring condition that gets recognized first, while the ADHD is missed entirely.

TheCDC’s December 2025 data brief confirms the scale of this overlap: among adults with diagnosed ADHD seen at health centers, 51.2% carried a co-diagnosis of an anxiety disorder, and 48.8% had a co-occurring mood disorder.

When the patient in front of you has anxiety and possible ADHD, a self-report checklist cannot tell you which is driving the symptoms — or whether both are. That requires a different kind of evaluation.

What Neuropsychological Testing Actually Measures

Neuropsychological testing takes the question out of the realm of self-perception and into the realm of measured performance. Rather than asking “how often do you lose things?” or “how difficult is it to sustain attention?”, objective testing presents a standardized task and measures how the brain actually responds — in real time, with millisecond precision.

For attention assessment, the gold standard objective tool is the T.O.V.A. (Test of Variables of Attention) — an FDA-cleared continuous performance test developed specifically to capture the neurological signature of attention difficulties.

Here’s what makes it categorically different from a questionnaire:

It removes recall bias. Self-report scales ask people to estimate their own frequency of symptoms — a task that is inherently imprecise, particularly for adults who have developed coping mechanisms over decades, or who are currently experiencing depression or anxiety that colors their self-perception. The T.O.V.A. doesn’t ask how you feel about your attention. It observes it directly.

It removes the influence of symptom overlap. A person with generalized anxiety disorder will almost certainly report difficulty concentrating on a checklist. But their brain’s performance on a sustained attention task may look quite different from someone with ADHD. The T.O.V.A. measures four specific variables — response time, response time variability, omissions (missed targets, reflecting inattention), and commissions (false presses, reflecting impulsivity) — and compares them against a large normative database of both non-ADHD individuals and those with confirmed ADHD diagnoses.

It is culture- and language-free. The T.O.V.A. uses simple geometric shapes, not language-dependent stimuli. This removes educational background, verbal ability, and cultural experience from the equation — a significant advantage for an adult population with diverse histories.

It has appeared in over 300 peer-reviewed studies and, as noted on The TOVA Company’s site, has been cleared for use as a medical device by the U.S. FDA, Health Canada, the European Union’s medical device regulators, and Australia’s Therapeutic Goods Administration.

ADHD vs. Anxiety vs. Depression: Why It Matters So Much to Get It Right

This isn’t an academic distinction. Getting the diagnosis wrong — in either direction — has real consequences.

Treating anxiety as ADHD and prescribing stimulant medication can worsen anxiety symptoms, disrupt sleep, and in some cases create cardiac risks. Treating ADHD as depression and using SSRIs alone often leaves the executive dysfunction untouched, leading patients to conclude that they are simply treatment-resistant — when in fact they never received the right intervention.

Research cited in the Missouri Medicine review of ADHD diagnostic trends documents that adults with untreated ADHD face elevated risk of unemployment, financial instability, relationship breakdown, substance use disorders, and depression — not because ADHD causes all of these, but because unaddressed executive dysfunction compounds every other life domain over time.

At the same time, the diagnostic challenge is genuinely difficult. As BJPsych Advances notes, “often, it is the comorbid conditions that are recognised and the symptoms of ADHD that are missed.” Both things are true: ADHD can be over-screened and under-diagnosed, depending on the tools used and the population being assessed.

This is precisely why the assessment methodology matters — and why a comprehensive evaluation that includes objective neuropsychological data, rather than checklists alone, represents a meaningfully higher standard of care.

What a Comprehensive Adult ADHD Evaluation Should Include

According to CHADD’s clinical guidelines, a rigorous adult ADHD evaluation should incorporate multiple sources and modalities, including:

• A structured clinical interview covering core symptom history, childhood onset, functional impairment across multiple life domains, and rule-out of differential diagnoses
• Standardized behavioral rating scales — used as one component, not the primary basis for diagnosis
• Collateral information where available (input from partners, family members, or longtime colleagues who can corroborate symptom history)
• Psychometric or neuropsychological testing to provide objective data on attention and executive function
• Screening for co-occurring conditions including anxiety, depression, sleep disorders, and trauma history

The T.O.V.A. serves the fourth function — providing the objective neuropsychological data point that self-report cannot. And critically, as both the TOVA Company and CHADD emphasize, no single test — including the T.O.V.A. — diagnoses ADHD. Only a qualified clinician, synthesizing all of the above, can make that determination.

What the T.O.V.A. does do is give the clinician something that questionnaires cannot: a performance-based window into how the brain regulates attention under sustained demand — the closest thing currently available to an objective neurological fingerprint of attentional functioning.

Signs That a More Advanced Evaluation May Be Right for You

Consider pursuing a comprehensive neuro-testing evaluation if:

• You’ve been treated for anxiety or depression without achieving meaningful improvement in concentration, task completion, or executive functioning
• A family member — particularly a child or sibling — has been diagnosed with ADHD, given its well-established heritability
• You’ve received conflicting opinions from different providers about whether ADHD is present
• You’ve taken an online ADHD quiz or self-report screener and tested positive, but haven’t had an objective clinical evaluation
• You’re experiencing significant real-world impairment — at work, in relationships, or financially — that doesn’t fully respond to treatment for other conditions
• You were assessed for ADHD as a child but never formally evaluated as an adult, and symptoms have evolved or worsened under adult demands

Women are particularly at risk of delayed diagnosis: research shows that adult women’s ADHD diagnoses rose 344% between 2007 and 2016 — largely because inattentive-type ADHD, which is more common in women, presents quietly and is more easily attributed to anxiety, perfectionism, or life circumstances than to a neurodevelopmental condition.

What to Expect from T.O.V.A. Testing at InDepth Therapy

At InDepth Therapy, T.O.V.A. testing is administered and interpreted by Bethany Blankenhiem, LPC, ADHD-CCSP, CACII — a Licensed Professional Counselor who holds the ADHD Certified Clinical Services Provider (ADHD-CCSP) designation through Evergreen Certifications, with 20 years of clinical experience and advanced training in ADHD, complex trauma, and co-occurring conditions including addiction.

The appointment takes approximately one hour. The T.O.V.A. itself runs 21.6 minutes — a sustained visual task that measures how the brain handles attention and impulse control in both high-demand and low-demand conditions. Following the assessment, your clinician reviews the results with you, explains what the data means in the context of your broader symptom history, and discusses recommended next steps.

For adults who go on to pursue treatment, InDepth’s integrative approach means that options extend beyond medication referrals. The practice offers individual therapy tailored to ADHD-related challenges, neurofeedback and brainmapping as a non-pharmacological option with a growing evidence base, and Brainspotting for adults whose ADHD history is entangled with trauma — which, in clinical practice, is more common than most people expect.

Testing costs:

• $225 for a 60-minute session
• $200 with a cash discount
• Medicaid accepted; superbills provided for other insurance plans

If you’ve already read our companion guide on what parents should know about T.O.V.A. testing for children, you’ll find the adult process similar in mechanics — but the clinical picture it’s embedded in is considerably more nuanced, which is exactly why the objective data matters so much.

The Bottom Line: Checklists Start the Conversation. Testing Advances It.

If you’ve been living with a diagnosis that doesn’t quite fit — or no diagnosis at all, just a persistent sense that something is off — a self-report questionnaire is a reasonable place to start. But it is not a place to stop.

The research is clear: symptom checklists cannot reliably distinguish ADHD from anxiety, depression, or other conditions with overlapping presentations. They were never designed to. They are screening tools, not diagnostic tools — and treating a positive screen as confirmation is one of the primary drivers of both misdiagnosis and missed diagnosis in adult ADHD.

Neuropsychological testing, combined with a thorough clinical evaluation by a specialist, is what moves you from “I think I might have ADHD” to “here is what my brain is actually doing, and here is a plan that addresses it.”

That clarity is available. And it’s closer than you might think.

Get a Comprehensive ADHD Evaluation in Broomfield

InDepth Therapy offers T.O.V.A. neuro-testing as part of a thorough, clinician-led ADHD evaluation for adults, at our office in Broomfield, Colorado, and with telehealth available statewide.

Broomfield: 1008 Depot Hill Road #200, Broomfield, CO 80020 

(720) 538-HELP (4357) 

HelpNow@indepththerapy.org

Schedule Your Adult ADHD Evaluation

About the Author

Bethany Blankenhiem, LPC, ADHD-CCSP, CACII is a Licensed Professional Counselor at InDepth Therapy with 20 years of experience in the psychology field. She holds the ADHD-CCSP (ADHD Certified Clinical Services Provider) designation through Evergreen Certifications and a CACII (Certified Addiction Counselor Level II) credential — a combination that reflects her deep clinical experience with the complex overlap between ADHD, co-occurring mental health conditions, and substance use.

Bethany is an Advanced Brainspotting trained clinician specializing in complex trauma, PTSD, grief, and the treatment of adults and young adults navigating major life transitions. She takes a strength-based, integrated, and deeply human approach to assessment and care — believing that accurate diagnosis is not the end of the conversation, but the beginning of it.

InDepth Therapy offers compassionate, trauma-informed mental health services, including individual therapy, couples counseling, family therapy, ADHD testing, neurofeedback, Brainspotting, and holistic studio services in Broomfield and Fort Collins, Colorado.