Beyond the Brochure: How Employers Can Choose the Right Adult ADHD Assessment

When organisations look to support employees with adult ADHD, the focus should be on the underlying assessment…

Trainers List · 13 Sep 2026

types of adhd in adults: When organisations look to support employees with adult ADHD, the focus should be on the underlying assessment methods and the outcomes they deliver, not merely the label on a brochure. The three primary subtypes of adult ADHD – inattentive, hyperactive‑impulsive and combined – each present distinct challenges, and the choice of diagnostic tool can affect how well a workplace programme matches those needs. For a quick overview of the subtypes, see the types of adhd in adults.

What the data say about adult ADHD subtypes

The online resource Adhdtest breaks down the three recognised adult ADHD subtypes and provides percentage estimates for each. According to the article, inattentive ADHD – often called ADD – accounts for approximately 33 % of all adult cases. Hyperactive‑impulsive ADHD makes up around 7 % of cases, while the combined type is the most common, representing 60 % of adult ADHD diagnoses.

These figures are useful for buyers because they highlight which symptom clusters are most prevalent in the adult workforce. A procurement team that selects a screening tool focused only on hyperactivity, for example, may miss the majority of employees whose primary difficulty is inattentiveness.

Why method and results matter more than branding

The commission brief stresses that buyers of ADHD assessment services should compare the scientific method and the reported outcomes of each tool, rather than rely on the name or branding that appears on a vendor’s brochure. This advice mirrors guidance from the UK National Health Service, which notes that diagnosis involves a combination of symptom checklists, clinical interviews and, where appropriate, rating scales (NHS.uk). The NHS also points out that most adults with ADHD display symptoms from more than one subtype, reinforcing the need for comprehensive assessment methods.

Similarly, the National Institute for Health and Care Excellence (NICE) recommends that any diagnostic pathway be transparent about the evidence base for its tools (NICE NG87). NICE’s guidance does not prescribe a particular commercial product, but it does require that the chosen method demonstrate reliability, validity and relevance to the adult population.

Implications for employers and public‑sector buyers

Employers who wish to implement mental‑health support programmes must first understand the prevalence of ADHD in the adult population. A study reported by King’s College London found that only 1.19 % of people in England have an ADHD diagnosis recorded in primary‑care data, far below international prevalence estimates (King’s College London). The same research highlighted a dramatic under‑diagnosis gap for older adults – just 0.05 % of those over 65 have a recorded diagnosis, suggesting that many employees may be living with untreated ADHD.

For public‑sector organisations, the under‑diagnosis data translate into a hidden risk: staff may be struggling with concentration, impulsivity or hyperactivity without appropriate support, potentially affecting productivity and safety. The Royal College of Psychiatrists advises that any workplace initiative be backed by professional medical input and that employees be encouraged to seek a qualified assessment (Royal College of Psychiatrists).

When choosing a provider, procurement teams should therefore request:

• Details of the diagnostic algorithm (e.g., DSM‑5 criteria, rating scales used).
• Evidence of validation studies in adult samples, preferably with breakdowns by subtype.
• Outcome data showing how the assessment informs treatment pathways or workplace accommodations.
• Cost‑effectiveness analyses that compare the tool’s price against the potential productivity gains from correctly identified cases.

These criteria move the conversation away from a simple “brand‑name” decision and toward a data‑driven evaluation of value.

Practical steps for a method‑focused procurement process

1. The table above can help translate prevalence percentages into head‑count estimates.

2. Benchmark providers. Compile a shortlist of assessment vendors and request their validation reports. Compare the proportion of each ADHD subtype that their tool reliably detects.

3. Pilot and evaluate. Run a small‑scale pilot with a representative employee sample. Measure outcomes such as diagnostic accuracy, employee satisfaction and any change in performance metrics.

4. Document the decision. Record the methodological criteria, the evidence supplied by the vendor and the pilot results. This documentation will be useful for future audits and for demonstrating compliance with NHS and NICE guidance.

For more detailed guidance on procurement best practices, see our internal resources on ADHD diagnosis trends and the Choosing an ADHD assessment guide.

By grounding the selection process in method and outcome data, employers can ensure that the support they provide aligns with the actual symptom profile of their workforce, rather than being limited by the marketing language on a brochure.