ADHD Functional Impairment Scale (ADHD-FIS)
Brief measure of functional impairment caused by ADHD symptoms.
Last reviewed: May 2026
The ADHD-FIS is a brief self-report measure designed to assess the functional impact of ADHD symptoms on daily life. Unlike symptom checklists that ask about behaviour frequency, the ADHD-FIS directly asks how much inattention and hyperactivity-impulsivity interfere with daily tasks, relationships, self-esteem, and overall functioning.
Scoring & Interpretation
Each item scored 0 (Not at all) to 4 (Extremely). Total score: sum of 6 items, range 0–24. Higher scores indicate greater functional impairment from ADHD symptoms.
| Score Range | Severity | Clinical Action |
|---|---|---|
| 0–4 | Minimal impairment | Functioning well — no intervention needed |
| 5–9 | Mild impairment | Monitor — consider support strategies |
| 10–14 | Moderate impairment | Functional impact significant — treatment indicated |
| 15–19 | Severe impairment | Major daily life impact — review treatment plan |
| 20–24 | Very severe impairment | Urgent — comprehensive support needed |
Internal consistency: α = 0.87. Responsive to treatment change (effect size d = 0.6 in medication trials). Correlates moderately with WFIRS-S total score (r = 0.72), confirming convergent validity with much lower patient burden.
When to Use This vs Alternatives
Use WFIRS-S when…
You need a comprehensive 7-domain impairment profile (69 items, 15 min). Use WFIRS-S at initial assessment for full picture; use ADHD-FIS (6 items, 2 min) for ongoing monitoring between sessions.
View WFIRS-S →Use ASRS when…
You need to screen for ADHD symptoms (frequency). The ASRS and ADHD-FIS are complementary: ASRS = "are symptoms present?", ADHD-FIS = "are symptoms causing functional problems?"
View ASRS →Use ACOS when…
Autism co-occurrence is suspected. The ADHD-FIS assumes pure ADHD — if traits overlap with autism, use ACOS first to clarify the diagnostic picture before tracking impairment.
View ACOS →See It in Action
- 1Mean score with severity band
- 2Subscale dividers (Daily Functioning, Work, Relationships, Wellbeing)
- 3Individual question responses with scoring badges
- 4One-click PDF export and email delivery
What It Measures
The ADHD-FIS is a brief self-report measure designed to assess the functional impact of ADHD symptoms on daily life. Unlike symptom checklists that ask about behaviour frequency, the ADHD-FIS directly asks how much inattention and hyperactivity-impulsivity interfere with daily tasks, relationships, self-esteem, and overall functioning. Its brevity (6 items) makes it ideal for routine monitoring alongside symptom measures.
When to Use the ADHD-FIS
Use the ADHD-FIS for quick routine monitoring of functional impairment across treatment. Administer at each session or monthly to track whether intervention (medication, coaching, therapy) is reducing real-world impact. Particularly useful as a brief companion to the ASRS — symptom frequency may remain stable while functional impact improves (or vice versa).
Who It's For
Adults aged 18+. Self-report. Suitable for clinical and community settings. Brief enough for repeated administration without patient burden. Can be used as a treatment outcome measure in medication trials or therapy monitoring.
Frequently Asked Questions
What is the ADHD-FIS?
The ADHD-FIS (ADHD Functional Impairment Scale) is a brief 6-item self-report measure that assesses how much ADHD symptoms interfere with daily functioning. It takes 2 minutes to complete and scores from 0–24, with higher scores indicating greater impairment.
How is the ADHD-FIS different from the WFIRS-S?
Both measure functional impairment from ADHD, but the ADHD-FIS is brief (6 items, 2 minutes) while the WFIRS-S is comprehensive (69 items, 15 minutes, 7 domains). Use WFIRS-S for detailed initial assessment; use ADHD-FIS for routine session-to-session monitoring.
Can the ADHD-FIS be used to track treatment progress?
Yes. The ADHD-FIS is responsive to treatment change (effect size d = 0.6 in medication trials). Its brevity makes it ideal for repeated administration — at intake, monthly, or at each session — to track whether functional impairment is reducing over time.
Use the ADHD-FIS in your practice
Available on the Starter plan. Instant scoring, severity bands, and PDF reports included. Patients complete it on their phone or computer. Scored the moment they hit submit.