Adult ADHD is increasingly discussed in public health circles, but the evidence base on how assessment services are chosen remains thin. The types of adhd in adults article outlines three primary sub‑types and their relative frequencies, while NHS and Royal College of Psychiatrists pages describe symptoms and clinical considerations. No source in the packet mentions procurement, buyer decision‑making or the need to compare assessment methods.

Sub‑type prevalence from the ADHD Test overview

The ADHD Test article breaks down adult ADHD into three categories:

• Inattentive type – approximately 33 % of adult cases.
• Hyper‑active‑impulsive type – around 7 % of adult cases.
• Combined type – the most common, accounting for about 60 % of adult cases.

These figures are presented without a specific time frame, but they constitute the only quantitative breakdown in the packet.

Clinical guidance from national health bodies

The NHS page on adult ADHD explains that most people exhibit symptoms of both inattentive and hyper‑active‑impulsive types, while acknowledging that some display only one set of symptoms. It stresses that a GP appointment is the first step toward diagnosis and that treatment options are tailored to the individual’s symptom profile.

Royal College of Psychiatrists (RCPsych) material frames ADHD as a neurodevelopmental disorder that typically begins in childhood and persists into adulthood, affecting concentration, energy levels and impulse control. The RCPsych page does not provide prevalence numbers, but it reinforces the clinical picture outlined by the NHS.

Professional perspectives beyond the clinical realm

A British Dietetic Association (BDA) article notes that dietitians are encountering more adult patients who self‑identify as having ADHD. The piece highlights the practical challenge for clinicians who lack formal training in neurodiversity and must learn on the job. It does not contain statistical data, but it adds a workplace dimension to the discussion of adult ADHD.

Evidence gap on procurement and buyer behaviour

Despite the detailed description of sub‑types and symptom management, the packet contains no mention of how organisations or individuals purchase ADHD assessment services. There is no discussion of methodological comparison, result validation or any procurement‑related obligations for employers. This absence is itself a factual observation: the research notes explicitly state that “the central claim about buyers needing to compare methods and results is not substantiated by any of the fetched source material.”

For readers seeking to understand the market for adult ADHD assessments, the lack of publicly available comparative data means decisions are likely based on brochure titles rather than independent performance metrics.

Comparative table of sub‑type shares

Source: ADHD Test article (2026‑09‑06). The table consolidates the three percentages for quick reference.

What remains unknown

The packet does not provide:

• Any figures on the number of assessment providers operating in the EU or UK.
• Data on the cost of different assessment methods.
• Evidence of regulatory guidance on comparing assessment outcomes.

These gaps suggest a need for systematic research into the procurement landscape for adult ADHD diagnostics.

Further reading

For broader context on social trends, see our recent pieces on youth friendship patterns (One in 20 English youths now have no close friends, IPPR finds) and nutrition research (Higher pre‑conception vitamin B12 linked to 66 % lower predicted birth‑defect risk).

External health resources include the NHS guide (NHS adult ADHD) and the Royal College of Psychiatrists overview (RCPsych ADHD in adults).

Until more detailed procurement data become available, buyers will have to rely on the limited clinical information currently published.