Weiss Functional Impairment Rating Scale — Self-Report (WFIRS-S)
Measures how ADHD symptoms affect daily functioning across 7 life domains.
Last reviewed: July 2026
- Full name
- Weiss Functional Impairment Rating Scale — Self-Report (WFIRS-S)
- Measures
- The WFIRS-S was developed by Margaret Weiss to measure functional impairment specifically associated with ADHD.
- Format
- 69 items · ~15 min · Self-report
- Score range
- 0.00 to 3.00
- Reliability
- Internal consistency: Cronbach's α = 0.95 (total), 0.80–0.93 (domains).
- Population
- Adults and adolescents aged 16+.
- Interpretation
- 0.00–0.99Minimal impairment
- 1.00–1.49Mild impairment
- 1.50–1.99Moderate impairment
- 2.00–3.00Severe impairment
Scoring & Interpretation
Each item scored 0 (Never) to 3 (Very Often). Domain scores are mean of non-missing items within that domain. Total score is mean of all items. Higher scores = greater impairment. Items endorsed as 2 or 3 are considered "clinically impaired" for that area.
| Score Range | Severity | Clinical Action |
|---|---|---|
| 0.00–0.99 | Minimal impairment | Within typical range; a mean around 0.65 has been reported as a screening flag (Weiss) |
| 1.00–1.49 | Mild impairment | Some domains affected — monitor and offer support strategies |
| 1.50–1.99 | Moderate impairment | Multiple domains affected — impairment consistent with ADHD |
| 2.00–3.00 | Severe impairment | Major functional disruption — treatment priority |
- Internal consistency: Cronbach's α = 0.95 (total), 0.80–0.93 (domains).
- Test-retest reliability: ICC = 0.85.
- Discriminates ADHD from healthy controls (d = 1.3–1.8 across domains).
- Sensitive to treatment change in medication trials (Weiss et al., 2018).
- Validated in 12 countries.
When to Use This vs Alternatives
| Instrument | Measures | Items | Reach for it when |
|---|---|---|---|
| WFIRS-S This page | ADHD | 69 | The comprehensive option you are reading about |
| ASRS | ADHD symptom frequency (screen) | 6–18 | You need to screen for ADHD symptoms (frequency), not measure impairment. The ASRS asks "how often do you have trouble concentrating?" — the WFIRS-S asks "how much does poor concentration affect your work, relationships, and daily life." |
| ADHD-FIS | Functional impact (screening) | 18 | You want a brief screening snapshot of functional impact (the ADHD-FIS, an original 18-item checklist) rather than the WFIRS-S's comprehensive, validated 7-domain profile. Use the WFIRS-S when you need a validated impairment measure. |
| ACOS | Overall symptom severity | 15 | You want to track overall ADHD symptom severity as an outcome over time rather than functional impairment. The ACOS gives a brief symptom-and-impact total; the WFIRS-S maps impairment across seven life domains. |
ADHD · 69 items
ADHD symptom frequency (screen) · 6–18 items
You need to screen for ADHD symptoms (frequency), not measure impairment. The ASRS asks "how often do you have trouble concentrating?" — the WFIRS-S asks "how much does poor concentration affect your work, relationships, and daily life."
Functional impact (screening) · 18 items
You want a brief screening snapshot of functional impact (the ADHD-FIS, an original 18-item checklist) rather than the WFIRS-S's comprehensive, validated 7-domain profile. Use the WFIRS-S when you need a validated impairment measure.
Overall symptom severity · 15 items
You want to track overall ADHD symptom severity as an outcome over time rather than functional impairment. The ACOS gives a brief symptom-and-impact total; the WFIRS-S maps impairment across seven life domains.
See It in Action
Sample: a completed WFIRS-S, scored and interpreted.
Moderate functional impairment. 2 of 7 domains fall in the Severe band, so the profile is uneven rather than evenly moderate.
Reassessed after a course of care: was 2.05, now 1.55 (lower than the earlier score).
By domain
- Family
- Mild · 10/21
- Work
- Severe · 21/30
- School
- Mild · 10/30
- Life Skills
- Moderate · 20/36
- Self-Concept
- Severe · 11/15
- Social
- Moderate · 14/27
- Risk
- Mild · 21/48
On ClientForms the total, its band and every domain flag are scored for you and ready to read or export as a PDF.
See the dashboard view
Synthetic sample for illustration — not a real patient.
What It Measures
Unlike symptom scales (which ask "how often"), the WFIRS-S asks "how much does this affect your life. " It covers 7 domains: Family, Work, School, Life Skills, Self-Concept, Social, and Risk-Taking. This makes it essential for demonstrating that ADHD symptoms cause clinically significant impairment — a DSM-5 diagnostic requirement.
- Family
- Relationships and responsibilities at home, with a partner, children and wider family.
- Work
- Performance, attendance and relationships in paid work.
- School
- Learning, study and performance in education or training.
- Life Skills
- Everyday self-management: sleep, money, health habits and getting things done.
- Self-Concept
- How the person sees themselves, their confidence and self-worth.
- Social
- Friendships, social activities and getting along with others.
- Risk-Taking
- Risk-taking and its consequences, including driving, substances and impulsive decisions.
When to Use the WFIRS-S
Use the WFIRS-S after confirming ADHD symptoms are present (e. g., via ASRS screen). DSM-5 requires evidence of functional impairment for diagnosis. The WFIRS-S provides this evidence across multiple life domains. Also useful for treatment monitoring — track whether medication or therapy reduces real-world impact over time.
Who It's For
Adults and adolescents aged 16+. Self-report. Validated in clinical ADHD populations and community samples. Available in 18 languages. For children under 16, use the parent-report version (WFIRS-P).
Frequently Asked Questions
What does the WFIRS-S measure?
The WFIRS-S measures functional impairment caused by ADHD symptoms across 7 life domains: Family, Work, School, Life Skills, Self-Concept, Social, and Risk-Taking. It answers "how much does ADHD affect your daily life" rather than just measuring symptom frequency.
How do you score the WFIRS-S?
Each of the 69 items is rated 0 (never) to 3 (very often). Domain scores are the mean of the items in that domain and the total is the mean of all items, so scores range from 0 to 3. Items a patient rates 2 or 3 mark areas of clinically significant impairment.
What is a clinically significant WFIRS-S score?
Higher mean scores indicate greater impairment, and any item rated 2 or 3 flags an area of concern. A mean item score around 0.65 has been reported as a screening threshold rather than a diagnostic cut-off; the WFIRS-S documents the functional impairment DSM-5 requires for an ADHD diagnosis, which the psychologist interprets in context.
What is the WFIRS-S cut-off score?
The WFIRS-S has no single official cut-off. As interpretive bands, a mean under 1.0 is minimal, 1.0–1.49 mild, 1.5–1.99 moderate and 2.0–3.0 severe, and any item rated 2 or 3 flags a clinically impaired area. Margaret Weiss reported a mean around 0.65 as a screening threshold rather than a diagnostic cut-off.
Why use the WFIRS-S alongside the ASRS?
DSM-5 requires both symptoms AND functional impairment for ADHD diagnosis. The ASRS confirms symptoms are present; the WFIRS-S documents that those symptoms cause real-world problems. Together they provide the full diagnostic picture.
Where can I get the WFIRS-S, and is it free to use?
The WFIRS-S is freely available for clinical use from Margaret Weiss and is included in ADHD assessment toolkits. On ClientForms you can send it to a patient, who completes it on their phone, and the seven domain scores and severity bands come back scored for you, ready to read or export.
Stop scoring the WFIRS-S by hand.
The total, the bands and the domain flags you just worked through, scored and laid out for you. New accounts get 30 days of full Professional access, no card.