What Is a Continuous Performance Test (CPT)?
A Continuous Performance Test (CPT) is a computer-administered task that measures sustained attention, impulse control, and response variability over time. Unlike rating scales, which rely on subjective recall from a patient, parent, or teacher, a CPT produces objective, quantifiable data — reaction times, omission errors, commission errors — that can be tracked and compared across sessions.
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Why clinicians use CPTs
ADHD rating scales are useful, but they’re inherently retrospective and subjective. A CPT adds a behavioral, in-the-moment measurement that complements clinical interviews and standardized questionnaires, particularly when:
- A diagnosis is ambiguous and additional objective data would help confirm or rule out ADHD
- A patient is starting or adjusting medication and treatment response needs to be tracked over time
- Symptom reporting is inconsistent across informants (e.g., parent vs. teacher)
What a CPT measures
Most CPTs, including AxonCPT, report on a consistent set of metrics:
- Omission errors — missed targets, associated with inattention
- Commission errors — responses to non-targets, associated with impulsivity
- Reaction time and variability — how consistently a patient responds over the course of the test
Where CPTs fit in an assessment workflow
A CPT is not a standalone diagnostic tool — it’s one input alongside clinical history, rating scales, and observation. Its value is in adding a repeatable, objective measure that can be re-administered during titration to track whether a treatment change is producing a measurable improvement in attention and impulse control.
For how CPT administration is coded and billed, see our ADHD testing CPT code guide.
If your patients take the test at home, see Remote CPT Testing: Validity and Environment Controls for what the research shows and how to standardize the testing environment. For what these tests cost a practice, see what objective ADHD testing costs clinicians. For how accurate CPTs actually are as a diagnostic tool, see CPT accuracy for ADHD: what the meta-analyses show, and for how the major products compare, see CPT tests compared: TOVA, Conners CPT 3, QbCheck, IVA-2. For a direct answer to whether a CPT alone can diagnose ADHD, see can a CPT diagnose ADHD? what it can and can’t show.