Weiss Functional Impairment Rating Scale
Self Report (WFIRS-S)
Rate how your emotional or behavioural difficulties have affected each area of your life over the last month. This scale measures functional impairment — how ADHD affects what you can actually do — and is used clinically to track whether treatment is making a real-world difference.
This is not a diagnostic tool. The WFIRS-S measures how ADHD is affecting your life, not whether you have ADHD. Share your results with your clinician — they can use this to monitor progress and inform treatment decisions. No data is stored or sent anywhere.
About the WFIRS-S
The Weiss Functional Impairment Rating Scale — Self Report was developed by Dr Margaret Danielle Weiss, MD PhD. It is a validated instrument used by clinicians to assess the real-world impact of ADHD across seven domains of daily life, and to track how that impact changes with treatment.
Unlike symptom rating scales, the WFIRS-S measures what ADHD prevents you from doing, not just how often symptoms occur. NICE NG87 — the national clinical guideline for ADHD — specifically recommends that clinicians use standard rating scales to record symptoms and functional impairment at baseline and at each stage of treatment (Recommendations 1.7.26 and 1.8.3). Completing this scale before a review appointment gives your clinician a structured picture of how ADHD is affecting your daily life in each domain.
Your WFIRS-S results
Items scored 2 (Often) or 3 (Very often) indicate areas of clinically significant difficulty. Print or save as PDF to share with your GP or clinician.
| Domain | Items scored 2 or 3 | Total score | Mean score |
|---|
How to use these results
- Items scored 2 (Often) or 3 (Very often) indicate areas where ADHD is causing clinically significant difficulty.
- A higher mean score in a domain indicates greater overall impairment in that area.
- If you are being treated for ADHD, repeat this scale regularly to track whether treatment is improving your functional outcomes. Bring results to your review appointments.
- Your clinician may use these scores to adjust your treatment. See our medications guide for information on ADHD treatment in Scotland.
- If you have not yet been assessed, see our NHS pathway or going private guides.
Copyright and permission
The WFIRS-S is copyright © Margaret Danielle Weiss, MD PhD. It is reproduced here with the express written permission of Dr Weiss, granted 25 June 2026. The scale may be used by clinicians and researchers free of charge. Contact Dr Weiss at margaret.weiss@icloud.com for permissions.
Clinical reference: Weiss MD. Weiss Functional Impairment Rating Scale — Self Report (WFIRS-S). University of British Columbia; 2000.
See also: NHS Scotland Right Decisions — ADHD clinical guidance · RCPsych CR235 — ADHD in Adults: Good Practice Guidance (2023)