QbCheck and Objective ADHD Testing: What It Adds and What It Does Not

QbCheck is a computer-based objective test used in some ADHD assessments. It measures attention, impulsivity and motor activity in a controlled task. It is not a diagnostic test on its own, but it can add useful information to a NICE-aligned assessment. This article explains what it does, where it fits, and what it cannot tell you.

What QbCheck is

QbCheck is a continuous performance test produced by Qbtech. It measures three things while the patient sits at a computer for around 15 to 20 minutes ^[3]:

• Attention. How well the patient detects target stimuli and rejects non-targets across the task.
• Impulsivity. How often the patient responds when they should not.
• Motor activity. Tracked through a head-mounted infrared marker, measuring small head movements during the task.

The results are reported against a normative dataset matched for age and sex. The output is a set of standardised scores rather than a yes or no answer.

A related test, QbTest, is the in-clinic equivalent used in NHS paediatric services in some areas. NICE published medical technologies guidance MTG6 in 2014, supporting the use of QbTest in children and adolescents as an adjunct to standard NICE-aligned assessment ^[2]. QbCheck is the remote, browser-based version intended for use at home or in a quiet setting and is used in adult and paediatric assessment.

Where QbCheck fits in a NICE-aligned assessment

NICE NG87 requires a thorough clinical interview, developmental history, informant input and structured tools ^[1]. QbCheck and QbTest sit in the structured-tools category. They are adjuncts, not replacements for the clinical interview.

In practice, NeuroFX uses QbCheck in approximately 10 to 15 percent of cases. It is offered when the clinical picture would benefit from objective corroboration, for example:

• Where there is uncertainty about whether attention difficulties reflect ADHD or something else
• Where the patient or family wants additional evidence to support an onward referral
• For paediatric assessment where school behaviour and home behaviour conflict
• As a baseline before starting medication, with a follow-up test to assess response
• Where shared care or insurance contexts ask for objective evidence

QbCheck is not routine. Most adult and paediatric assessments do not require it. Where it is offered at NeuroFX, the current fee is £129.

What QbCheck does well

• It produces objective data in a standardised format, which is useful for triangulation with self-report and clinical interview.
• It can detect attention and motor activity patterns that the patient may not be conscious of.
• It is normed against age and sex, which makes scores interpretable in context.
• It can be used to measure response to medication, with before-and-after testing.
• It is robust to language barriers in the way an interview is not, which can be useful in some clinical contexts.

What QbCheck does not do

• It does not diagnose ADHD on its own. NICE explicitly states that objective tests support but do not replace clinical assessment ^{[1, 2]}.
• It does not rule out ADHD. A "normal" QbCheck in someone who otherwise meets criteria does not exclude the diagnosis. Attention can be intact in the lab and impaired in real life; this is one of the things ADHD attention does.
• It is not perfectly sensitive or specific. Independent reviews show that continuous performance tests, including QbCheck, miss some patients with clear ADHD and flag some patients who do not have it ^[3].
• It does not capture the full picture. ADHD is more than attention and motor activity; emotional dysregulation, working memory and executive function are not measured.
• It is not a substitute for paying attention in real life. Patients sometimes worry that a "normal" QbCheck means they cannot have ADHD because they did well on the task. The opposite can also be true: patients sometimes worry an "abnormal" result confirms they have ADHD when the clinical picture is something else.

When QbCheck is most useful

A few scenarios where QbCheck genuinely adds value:

Diagnostic uncertainty

Where the clinical picture is ambiguous and additional objective evidence would help, QbCheck can swing the balance. For example, in adults where chronic anxiety and ADHD overlap, a QbCheck pattern can sometimes clarify the relative contribution.

Paediatric assessment with conflicting school and home reports

NICE MTG6 specifically supports the use of QbTest in children and adolescents alongside standard NICE assessment, particularly where the clinical picture is ambiguous ^[2]. Where school reports and home reports conflict, QbCheck adds an objective layer.

Medication titration

A baseline QbCheck before starting medication, with a follow-up at four to six weeks, can give an objective measure of response. This is most useful where the clinical response is unclear or where the patient and clinician want a quantitative anchor.

Onward referrals or insurance

Some shared care arrangements, employer adjustment processes or insurance contexts ask for objective evidence. QbCheck can provide this.

When QbCheck is not the right choice

• The clinical picture is already clear and a NICE-aligned interview-based assessment has answered the question.
• The patient is highly anxious about computer-based testing in a way that would compromise the result.
• The patient has co-occurring conditions (severe anxiety, mood disorder in acute phase) that would make the result hard to interpret.
• The additional cost is not justified by what the test would add for that specific patient.

The decision to use QbCheck is a clinical one, made by the assessing clinician with the patient.

What this means in practice

• QbCheck adds information; it does not diagnose ADHD.
• Most ADHD assessments do not need it. Where it would help, your clinician will offer it.
• A "normal" QbCheck in someone who otherwise meets criteria does not rule out ADHD.
• An "abnormal" QbCheck in someone who does not meet other criteria does not confirm ADHD.
• The test is most useful for triangulation, for paediatric assessments where reports conflict, and for measuring medication response.

When to speak to a professional

If you are unsure whether QbCheck would be useful in your case, ask the assessing clinician. NeuroFX offers QbCheck where it adds value to a NICE-aligned assessment, including for private adult ADHD assessment and private paediatric ADHD assessment at our Bedford clinic. Seek same-day help via 111 (or 999 in an emergency) for any mental health crisis.

Sources

1. NICE. Attention deficit hyperactivity disorder: diagnosis and management. NG87. National Institute for Health and Care Excellence. https://www.nice.org.uk/guidance/ng87
2. NICE. Medical technologies guidance MTG6: The QbTest for the assessment of attention deficit hyperactivity disorder (ADHD). 2014. https://www.nice.org.uk/guidance/mtg6
3. Hall CL, Valentine AZ, Groom MJ, et al. The clinical utility of the continuous performance test and objective measures of activity for diagnosing and monitoring ADHD in children: a systematic review. European Child and Adolescent Psychiatry. 2016;25(7):677-699.
4. Kooij JJS, Bijlenga D, Salerno L, et al. Updated European Consensus Statement on diagnosis and treatment of adult ADHD. European Psychiatry. 2019;56:14-34.