Three months. 337 adults with confirmed ADHD diagnoses. An app. And a Cohen’s d of 0.85.

That last number is the one that matters. d=0.85 is large by any clinical standard. It’s the same territory as the effect sizes you see in adult ADHD medication trials. Not “comparable to a meditation app.” On the same level as pharmacological intervention by raw effect size.

The March 2026 Attexis RCT published in Psychological Medicine is the first trial to prove clinical efficacy for a digital CBT tool specifically in adult ADHD at this scale. Adult ADHD prescriptions more than doubled since COVID, but access to non-pharmacological support hasn’t kept pace. The waitlist to see an ADHD-trained CBT therapist in most cities is months long.

This data changes that calculation. But only if you know how to read it correctly. Reading the headline stat and moving on misses the actual value: the RCT gives you a framework for deciding exactly where Attexis fits in your support stack, and where it doesn’t.

TL;DR for ADHD Brains

What	The Data
Trial size	337 adults with confirmed ADHD
Duration	3 months (6-month follow-up)
Effect size	Cohen’s d=0.85 vs. treatment-as-usual
Symptom drop	–5.0 points on ASRS
Gains stable at	6-month follow-up
Regulatory status	DiGA (Germany); covered by statutory health insurers since Aug 2025
AI diagnosis accuracy	93.61% in separate study

One-sentence verdict: The clinical evidence is real. Now the question is whether Attexis belongs in YOUR stack, and if so, where.

Best for: Adults with diagnosed ADHD who’ve hit a ceiling with productivity tools alone, or who can’t access regular face-to-face CBT Skip if: You’re actively in in-person CBT that’s working. This likely overlaps too much to stack efficiently.

What d=0.85 Actually Means for a Non-Statistician

Cohen’s d measures how far apart two groups are in standard deviation units. A d of 0.2 is small. A d of 0.5 is medium. A d of 0.8 and above is large.

d=0.85 is not “the app kind of helped.” To give you a concrete anchor: well-designed adult ADHD stimulant trials typically land between d=0.5 and d=0.9 on symptom outcomes. The Attexis result is inside that range, achieved with structured cognitive behavioral modules rather than pharmacology.

The –5.0 point drop on the ASRS (Adult ADHD Self-Report Scale) translates to crossing clinical thresholds for a meaningful portion of participants, not just a statistically detectable whisper of change.

And the 6-month follow-up data is the part that should get your attention. The gains held. Without ongoing active treatment. That’s different from a medication study, where your symptoms return when you stop taking the pill. CBT-based gains, when they stick, stick differently because you’re building cognitive patterns, not just managing symptoms pharmacologically.

Why the Germany DiGA Listing Matters More Than You’d Think

Attexis was permanently listed in Germany’s DiGA (Digitale Gesundheitsanwendungen) directory and covered by statutory health insurers since August 2025.

The DiGA pathway is the most rigorous regulatory framework for digital health apps in the world right now. To get listed, apps must demonstrate clinical benefit through real-world evidence, not just safety. The permanent listing (as opposed to provisional) means Attexis cleared the full evidentiary bar.

Germany’s statutory health insurance covers roughly 90% of the population. Being on the DiGA list with permanent status means roughly 73 million people can access this app at no out-of-pocket cost. That’s not a marketing achievement. It’s a regulatory validation that the clinical evidence met an independent government standard.

For people outside Germany: the app is available internationally via app stores, though cost varies and no equivalent regulatory endorsement exists yet in the US or UK. The FDA’s slow pace with digital therapeutics classification is a separate issue from clinical evidence quality.

The Diagnosis Gap This App Addresses

A separate 2025 study (not the RCT) showed AI-assisted ADHD diagnosis achieving 93.61% accuracy for adult ADHD identification.

Why does this appear in the same conversation as Attexis? Because adult ADHD prescriptions more than doubled after COVID, and clinical capacity hasn’t kept pace. Waitlists for adult ADHD evaluations in the UK stretch to 3–7 years in many NHS trusts. US wait times in many states run 6–18 months for specialized evaluation.

The diagnosis bottleneck creates a secondary problem: adults who have been diagnosed and are waiting for follow-up CBT support, or who were diagnosed but never connected to non-pharmacological interventions. Attexis specifically targets that gap. It’s not an alternative to diagnosis. You need confirmed ADHD for this app’s evidence to apply to you. But once diagnosed, access to evidence-based CBT no longer requires finding a therapist with the right specialty, an open slot, and an affordable fee.

Your Treatment Stack Decision Framework

Here’s how I’d think about where Attexis belongs, based on the RCT evidence and what CBT for ADHD actually addresses:

If your current stack is: medication only

This is the most common scenario for adult ADHD management. Medication handles the neurochemistry; it doesn’t address the behavioral patterns built up over years of unmanaged ADHD. The avoidance loops, the time blindness adaptations, the shame-response to executive function failures: these don’t automatically resolve when the medication starts working.

Attexis fills exactly this gap. The RCT’s treatment-as-usual control group was essentially “medication and/or coaching without structured CBT.” The experimental group got Attexis on top of whatever they were already doing. The d=0.85 effect represents what structured digital CBT adds to the baseline.

If your current stack is: productivity tools only

You’re managing the symptoms at the accommodation layer, using external systems to compensate for executive function gaps. This is legitimate and worth doing. Evidence-based productivity strategies and AI task management tools genuinely reduce friction.

But accommodation tools don’t address the internal patterns. The self-interruption when something feels hard. The avoidance that feels like laziness but is actually a cognitive protection mechanism. CBT targets those directly. If you’ve built a solid tool stack and still feel like you’re white-knuckling through tasks that shouldn’t require this much effort, that’s a signal that the cognitive layer hasn’t been addressed.

If your current stack is: no formal support

The unmet demand is real. Adult ADHD prescriptions more than doubled since COVID. Non-pharmacological support has not scaled anywhere near proportionally. If you’re one of the adults who has a diagnosis but hasn’t connected to either medication or structured CBT, Attexis represents something genuinely new: clinical-grade CBT intervention that doesn’t require you to get on a waitlist, find insurance coverage, or commute to a therapist’s office.

The evidence supports giving it a real try. Not as a replacement for professional support if you can access it, but as a legitimate clinical intervention in its own right.

If you’re already in face-to-face CBT

The evidence doesn’t support stacking Attexis on top of active in-person CBT. The content overlaps significantly. Unless your therapist is explicitly not ADHD-focused and you want to supplement with ADHD-specific CBT protocols, this is probably redundant.

What CBT for ADHD Actually Targets (And Why Apps Can Deliver It)

CBT for ADHD is not generic talk therapy. It’s a structured protocol targeting specific executive function breakdowns:

• Task initiation failure: Why starting is harder than doing. The CBT approach builds specific response patterns for the moment before avoidance wins.
• Time perception distortion: The ADHD brain genuinely experiences time differently. CBT modules address the gap between how long you think something takes and how long it actually takes.
• Procrastination-shame cycles: Avoidance creates shame; shame creates more avoidance. Breaking the cycle is a trainable cognitive skill.
• Emotional dysregulation responses: The frustration, rejection sensitivity, and emotional flooding that ADHD adults experience at higher rates.

What makes an app viable for delivering these protocols (rather than just repackaging them as tips) is the structured, sequential module design. Attexis was built with psychotherapist-designed content following validated CBT protocols. It’s not a chatbot. It doesn’t adapt dynamically based on your conversation. It delivers structured modules in the same theoretical framework a trained CBT therapist would use.

The RCT demonstrated that this delivery mechanism achieves outcomes comparable to face-to-face CBT benchmarks. That’s the evidence gap that’s been filled.

How the 6-Month Follow-Up Data Changes the Cost-Benefit Calculation

Most digital health trials measure outcomes at treatment end. The 6-month follow-up showing stable gains is a different data point.

For the treatment-stack decision, this matters because it affects the time investment math. Three months of consistent engagement with 10–15 minute daily modules is the evidence-based protocol. If the gains at 3 months are substantially maintained at 6 months without continued intensive use, that changes how you think about the opportunity cost of the initial investment.

Compare this to the ongoing cost of face-to-face CBT: in the US, 12 sessions typically runs $1,800–$4,200 out of pocket when you’re paying without insurance, and results require sustained engagement over that period. The Attexis cost structure (covered by German statutory insurance; subscription pricing outside Germany) represents a meaningfully different access model.

For adults who are also managing medication access challenges or building systems that don’t rely on prescription availability, the stable-at-6-months data makes Attexis more relevant, not less.

How to Run Your Own Clinical Assessment

Before downloading the app, do this: take the ASRS-v1.1 screener and record your baseline score. You don’t need to self-diagnose with it. But having a number at baseline means you’ll have actual data at 30, 60, and 90 days rather than just a vague impression.

The trial used the ASRS as its primary outcome measure precisely because it’s validated and trackable over time. Replicating that structure in your own use gives you something the app itself doesn’t provide: a personal evidence base for whether it’s working for your specific brain.

Practical setup:

1. Download Attexis (iOS/Android). German users: request coverage via your health insurer’s app portal.
2. Complete the onboarding assessment honestly. The tendency to present better than you’re actually doing is real and will result in modules that underserve your actual needs.
3. Block 10–15 minutes daily for the first three weeks. Morning works better than evening for most ADHD adults. Task initiation is a module focus, and the irony of procrastinating on the task-initiation module is real.
4. At day 30, re-take the ASRS and compare. If you’re seeing movement of 3+ points, continue. If nothing has moved at all, that’s data worth examining: either the delivery format isn’t working for your brain, or something in your engagement pattern needs adjusting.

For how digital CBT fits alongside AI-powered coaching tools, the best AI ADHD coaching apps roundup covers what each category actually does and how they layer without overlap.

The Honest Bottom Line

The March 2026 Attexis RCT moved this from “promising digital health experiment” to “clinical evidence with real regulatory weight.” The effect size is large. The gains are durable at 6 months. Germany’s most rigorous digital health framework endorsed it with permanent listing.

What the data doesn’t do: guarantee it works for you specifically. Individual response to CBT (digital or otherwise) varies. Some ADHD presentations (particularly those where emotional dysregulation or RSD is the dominant challenge) may need more targeted support than any app can provide.

But the standard has changed. If your treatment stack doesn’t include some form of structured CBT, and your ADHD is affecting your daily function, the evidence now says you’re missing the best-supported non-pharmacological option available. Whether you access it through Attexis or a therapist depends on what you can actually reach.

Start with what’s reachable.

Your next 15 minutes: Take the ASRS screener and record your baseline score. Download Attexis. Start the onboarding assessment. Three months from now, you’ll have actual data on whether this moved the needle, not just a vague sense of “I’ve been trying harder.”

That’s the kind of self-experiment worth running.

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The Attexis RCT enrolled 337 adults with confirmed ADHD diagnoses. Primary outcome: –5.0 ASRS points vs. treatment-as-usual (Cohen’s d=0.85, p<.001) at 3 months, with gains stable at 6-month follow-up. Published in Psychological Medicine, March 2026. For the full RCT data, see Psychological Medicine. ASRS-v1.1 screener available at CHADD.