ADHD assessment has the same underlying diagnostic criteria across ages (DSM-5-TR requires childhood-onset symptoms in everyone), but the practical pathways differ substantially between adults and children. Understanding which one you're navigating helps set expectations for who to see, what to expect, and what diagnostic instruments apply.
Pediatric assessment — what's different
Multiple informants
Pediatric ADHD assessment relies on observation and rating from multiple sources — parent, teacher, sometimes coach or other regular caregivers. This is built into the diagnostic process. Standard pediatric instruments (Vanderbilt scales, Conners 3) come in parent and teacher versions specifically.
Developmental and family history
More extensive than for adults. Pregnancy, birth, early developmental milestones, family history of ADHD/learning disabilities/mental health, school history with academic and behavioral records.
Provider type
Pediatricians are commonly first-line for pediatric ADHD. Developmental-behavioral pediatricians, child psychologists, and child psychiatrists handle more complex cases. Adult-focused psychiatrists generally don't see children.
School involvement
Often part of the assessment. Teacher rating scales (Vanderbilt, BASC), classroom observation in some cases, school records review. After diagnosis, an IEP or 504 plan may be developed to provide accommodations.
Treatment cadence
Closer follow-up than adults — children often have monthly visits during titration, then quarterly. Growth tracking matters because stimulants can affect appetite and weight. Annual check-ins on growth, mood, and school function continue while on treatment.
Adult assessment — what's different
Self-report dominant
Adults are usually their own primary informant. Some clinicians ask for collateral information from a partner, family member, or close friend; many don't. The DSM-5-TR criterion of childhood-onset is established by retrospective self-report — sometimes corroborated by old school records or family members.
Differential diagnosis is harder
Adults have had decades to accumulate other conditions that look like ADHD: anxiety, depression, sleep disorders, trauma, substance use, hormonal changes. A good adult assessment screens for all of these. Pediatric differentials exist but the constellation of conditions is narrower.
Provider type
Psychiatrists, psychologists, primary care providers, psychiatric nurse practitioners. In the US, telehealth services have expanded adult access dramatically. In the UK, NHS adult ADHD services are often heavily backlogged, with private and Right To Choose pathways frequently used.
Functional context
The clinician evaluates current functional impairment in adult contexts: work, relationships, daily-life management, finances, parenting. The DSM-5-TR requires symptoms causing functional impairment, not just symptom presence.
Treatment cadence
Once stable, adult follow-up can be quarterly or even less frequent. Some adults see their prescriber every 3 months for a brief check-in plus prescription renewal. Others have shared-care arrangements where a psychiatrist initiates treatment and a primary care provider continues prescribing.
The adolescent middle
Adolescents (13–17) span pediatric and adult pathways. Family involvement is usually still part of the assessment, but the adolescent's own report becomes increasingly central. Some clinicians who see only younger children won't see adolescents; some adult psychiatrists will see older adolescents but not younger children. Many "ADHD specialty" services explicitly cover ages 6+ or 13+ as their range.
Re-evaluation in transitions
A child diagnosed at age 8 doesn't automatically continue with the same diagnosis at age 25. Some adults previously diagnosed with childhood ADHD genuinely no longer meet adult criteria; others continue to meet criteria with different symptom emphasis (less hyperactivity, more inattention, more executive dysfunction). Transitions from pediatric to adult care often involve some re-evaluation, not just continuation.
Pathway summary
- Suspecting ADHD in a child: start with the pediatrician. They can either assess directly, refer to a developmental-behavioral pediatrician or child psychiatrist, or coordinate with school. Vanderbilt rating scales are the most common starting instrument.
- Suspecting ADHD in an adolescent: usually still through the pediatrician or family medicine provider. School involvement remains useful. Some practices transition adolescents to adult-style assessment around 16–18.
- Suspecting ADHD in yourself as an adult: primary care, telehealth ADHD specialty service, or psychiatrist. ASRS or BAARS-IV scales are common adult instruments. Differential evaluation is critical.
The cost & pathway tool shows realistic timelines and costs for adult assessment by country and insurance situation.