How is ADHD diagnosed?
ADHD diagnosis requires three things: persistent symptoms across multiple settings (home, work), onset before age 12, and functional impairment — the symptoms must actually interfere with daily life, not just be present. There is no single definitive test.
| Tool | What it measures | Used by |
|---|---|---|
| Clinical interview | Symptom history, childhood onset, functional impact | Psychiatrists, psychologists |
| Rating scales (Conners, ASRS, Brown) | Self/observer-reported symptom frequency and severity | All clinicians |
| CPT (Continuous Performance Test) | Objective attention and impulsivity metrics | Neuropsychologists |
| Neuropsychological battery | Working memory, processing speed, executive function | Neuropsychologists |
| Medical history | Rule out thyroid, sleep disorders, anxiety, depression | GPs, psychiatrists |
| Brain imaging | NOT used for diagnosis — research only | Research settings |
The Attention & Focus test uses a CPT paradigm — take it before a clinical appointment to get objective data to share with a clinician. It measures omission errors (missed targets — inattention) and commission errors (false responses — impulsivity), the same metrics used in clinical CPT assessment.
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Based on the clinical CPT — free, no account needed.
Quick Answer
ADHD diagnosis requires persistent symptoms across multiple settings (home, work, school), onset before age 12, and functional impairment. Standard tools include clinical interview, rating scales (Conners, ASRS), and often neuropsychological testing including attention and working memory tasks.
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