Attention-deficit hyperactivity disorder (ADHD) screening requests have surged across care settings for various reasons. The consequences of missing the diagnosis are well documented, as ADHD that goes unrecognized is associated with poorer mental and physical health outcomes, substance misuse, and disrupted education and working life. However, ADHD is not diagnosed by any one test.
The time-consuming norm is to gather and interpret self-reported information through interviews and standardized, symptom-based questionnaires, then using clinical judgment and experience to guide the diagnosis. Consequently, busy clinicians may feel overwhelmed and wish for something objective to support the ADHD diagnosis.
Objective testing can add evidence to this picture and ease some of the uncertainty behind overdiagnosis concerns. QbTest is one such tool. This article explains what a QbTest measures, the quality of the evidence behind it, and where objective data fits in a rigorous ADHD evaluation.
Article Highlights
- QbTest pairs a continuous performance test with infrared motion tracking to quantify behavior associated with inattention, impulsivity, and hyperactivity, and typically takes about 20 minutes to complete.
- A 2023 meta-analysis of 15 studies found it correctly identified about 78% of ADHD cases and 70% of those without. The authors concluded that this can add useful information but is not accurate enough to separate ADHD from other conditions on its own.
- Motion tracking and cognitive assessment measure different things. The former captures observable movement; the latter gives a detailed profile of working memory, executive function, and inhibition.
What is QbTest?
QbTest is an ADHD testing aid cleared by the Food and Drug Administration (FDA) and developed for use with individuals ages 6 to 60. In practice, this computer-based tool typically takes about 20 minutes to complete, but many allow 30 to 40 minutes in total for the setup.
What QbTest measures
QbTest is designed to quantify behavior associated with 3 core symptoms of ADHD: inattention, impulsivity, and hyperactivity. To do this, it uses a continuous performance test (CPT) to quantify reaction time and errors, while infrared motion tracking monitors motor activity levels.
How QbTest works
During the QbTest assessment, patients complete tasks using a hand-held responder button linked to a computer screen, while their movement is monitored. This is intended to capture 3 core symptoms in a single session.
The CPT component
The CPT captures reaction times (speed of responding), omission errors (failing to respond), and commission errors (inappropriate responses) through an age-specific version of QbTest’s CPT:
- The version for children aged 7 to 12 years uses a simple target detection, or go/no-go task.
- The version for those aged 12+ years adds a working memory component with a one-back test, where patients watch a stream of colored squares and circles and respond whenever two consecutive stimuli match in both color and shape.
The activity tracking component
During the CPT, the patient wears a forehead reflector, and the infrared camera monitors motor activity by tracking the reflector's movement.
QbTest in-clinic testing vs. QbCheck test
The infrared hardware limits QbTest to in-clinic use. QbCheck is a separate product from Qbtech that registers movement through the computer's built-in webcam and can be administered remotely. QbCheck also uses the patient’s own keyboard for responses instead of unique hardware, and produces a different report from QbTest’s.
Reading QbTest results
The Qb system converts raw performance measures into a visual report summary of 3 core ADHD symptoms. Scores are then compared against a normative dataset of 1,307 individuals from Sweden and Germany, matched by age and sex.
What the evidence says about clinical utility
QbTest has been evaluated in independent research, and regulatory guideline bodies have weighed in on its use:
- The FDA’s description of the intended use states that “QbTest… (is an) aid in the clinical assessment of ADHD and in the evaluation of treatment interventions in patients with ADHD…,” not a standalone diagnostic tool.
- The United Kingdom (UK) based National Institute for Health and Care Excellence (NICE) recommends QbTest as an ADHD diagnostic aid only for 6- to 17-year-olds, prioritizing clinician judgment as the baseline.
- In 2023, a systematic review and meta-analysis pooled 15 studies and 2,058 participants to test how well QbTest distinguishes ADHD on its own:
- The overall performance reached acceptable sensitivity and specificity, correctly identifying about 78% of ADHD cases and 70% of those without.
- The individual subscales for activity, inattention, and impulsivity reached low-to-moderate sensitivity and moderate-to-good specificity.
- The authors concluded that QbTest can add useful information but is not accurate enough on its own to separate ADHD from other conditions, and should not replace a full clinical assessment.
- QbTest may also suit some patients better than others. Completing it may be hard for very young children and for people with physical disabilities or learning difficulties, and the forehead marker may be poorly tolerated by autistic children or those with sensory sensitivities.
Where objective data fits in the ADHD assessment process
An ADHD diagnosis is clinical, as guidelines emphasize the need to meet the Diagnostic and Statistical Manual of Mental Disorders, 5th ed. (DSM-5-TR) criteria.
Most of the supporting evidence, however, is subjective:
- Developmental history of early life behaviors and milestones
- Clinical interviews
- Rating scales and questionnaires:
This history lets the clinician map symptoms against the DSM criteria, but self-report also carries a risk of misdiagnosis or overdiagnosis. Including objective evidence as support can strengthen diagnostic confidence.
Equally important, accurately excluding ADHD during the diagnostic process spares patients from treatment they don't need.
Together, clinical interviews, rating scales, and objective, measurable outcomes form a more complete picture in an ADHD assessment than any one source alone.
Cognitive assessment and motion-based testing measure different things
Objective testing strengthens that picture, and different objective tools capture different symptoms. Where motion tracking passively measures aspects of hyperactivity, the CPT measures core symptoms through the patient’s active responses. The Creyos ADHD assessment tool profiles a variety of cognitive functions affected in ADHD, including attention, inhibition, working memory, and executive function.
The Creyos computer-based ADHD assessment tool measures not only the same aspects of attention, focus, and inhibition as QbTest, but also provides essential insights into working memory and executive function.
The Creyos ADHD protocol is built around 14 markers, which are specific cognitive performance metrics associated with an ADHD diagnosis. To identify them, Creyos reviewed over 100 peer-reviewed papers and drew the markers from its cognitive tasks:
- 10 markers from 4 existing Creyos cognitive tasks: Spatial Planning, Token Search, Feature Match, and Double Trouble
- 4 markers from the Sustained Attention to Response Task (SART)—a CPT similar to the task included with QbTest
The assessment can also be tailored to include age-appropriate questionnaires for adults and children, and it takes under 25 minutes to complete.
The Creyos platform does not track motor activity, which is only an indirect measure of hyperactivity in everyday life, and is susceptible to issues with setting up tracking hardware or a webcam. Instead, Creyos incorporates reports from patients or parents to capture hyperactivity symptoms, and provides a detailed profile of working memory, executive function, and attention that motion tracking is not designed to capture.
The full Creyos ADHD protocol takes a comparable amount of time to QbTest while measuring across several cognitive domains rather than a single task, and it runs on a standard computer or tablet with no specialized hardware, in the clinic or via telehealth.
Choosing an objective measure for your practice
Objective data gives clinicians measurable evidence to sit alongside patient history, clinical interview, and rating scales. While motion-based systems can quantify some behavioral symptoms of hyperactivity, cognitive assessment profiles the underlying functions impaired in individuals with ADHD, including working memory, executive function, and inhibition. The right choice depends on which of those metrics a practice needs to document, and on whether the assessment has to run in a clinic or have the flexibility to travel with the patient.
Written by Dr. Dorianne Green, Medical Writer
Dr. Green is a physician-turned-medical writer with over two decades of clinical experience in primary care and as chief clinician for a geriatric and dementia care unit. Her special interests are mental health and trauma-informed care.