Patient-reported outcome measure
FAAM Calculator
Foot and Ankle Ability Measure
The FAAM is a 29-item patient-reported questionnaire for musculoskeletal disorders of the leg, foot and ankle that produces two separate subscale scores — Activities of Daily Living from 21 items and Sports from 8 items — each expressed from 0% (unable to perform the listed activities) to 100% (no limitation).
What the FAAM score means
FAAM scores run from 0 to 100, where a higher score is better. The bands below are conventional reporting categories, not diagnostic cut-offs.
- Severe limitation0–24.9
Most of the listed activities cannot be performed, or can only be performed with extreme difficulty.
- Marked limitation25–49.9
- Moderate limitation50–74.9
- Mild limitation75–89.9
- Minimal to no limitation90–100
Function at or close to the ceiling of the subscale. In athletes the ADL subscale reaches this range routinely, which is why the Sports subscale is the more useful endpoint in that group.
Clinically important thresholds
A change in score only matters if it exceeds the smallest difference patients actually notice. Every threshold below is reported with the population it was derived in — a threshold quoted without its population is not usable.
| Type | Value | Subscale | Population | Follow-up | Source |
|---|---|---|---|---|---|
| MCID | 8 points | ADL | Adults with a broad range of leg, foot and ankle musculoskeletal disorders who self-rated as improved | — | Martin RL 2005 |
| MCID | 9 points | Sports | Adults with a broad range of leg, foot and ankle musculoskeletal disorders who self-rated as improved | — | Martin RL 2005 |
| MDC | 5.7 points | ADL | Adults with leg, foot and ankle musculoskeletal disorders, stable between administrations | — | Martin RL 2005 |
| MDC | 12.3 points | Sports | Adults with leg, foot and ankle musculoskeletal disorders, stable between administrations | — | Martin RL 2005 |
MCID is the smallest change a patient perceives as meaningful. PASS is the score above which patients consider their state acceptable. SCB is a substantial rather than minimal benefit. MDC is the smallest change exceeding measurement error.
How the score is calculated
Stated in full so the calculation can be independently checked, and reproduced by hand if needed.
Each of the 29 items is scored from 4 (no difficulty at all) down to 0 (unable to do), so a higher raw score means better function. The two subscales are scored separately and never combined. The Activities of Daily Living subscale has 21 items and a maximum of 84 points; the Sports subscale has 8 items and a maximum of 32 points. For each subscale, the answered item scores are summed and expressed as a percentage of the maximum still available: score = (sum of item scores ÷ (4 × number of items answered)) × 100. An item left blank or marked not applicable is removed from both the numerator and the denominator, which is identical to subtracting 4 points from that subscale's maximum. A score of 100% means no limitation and 0% means unable to perform any of the listed activities. The two 0–100 global rating questions and the four-level overall rating are recorded but are not part of either calculation.
Missing data
Blank and not-applicable responses are excluded from the denominator rather than scored zero. The developer's completion rule is that 20 of the 21 Activities of Daily Living items and 7 of the 8 Sports items must be answered, so a subscale tolerates at most one missing or not-applicable response and is otherwise not calculated. The two subscales stand independently — either can still be reported when the other cannot be scored, which is the usual situation in sedentary patients who leave the Sports items blank, and in whom the Sports subscale should not be reported at all rather than reported from two or three items.
Instrument profile
- Developer
- RobRoy L. Martin, James J. Irrgang, Ray G. Burdett, Stephen F. Conti, Jessie M. Van Swearingen
- Institution
- University of Pittsburgh, United States
- First published
- 2005
- Items
- 29
- Response format
- 5-point difficulty scale scored 4 (no difficulty) to 0 (unable to do), plus a not-applicable option
- Score range
- 0 to 100
- Direction
- Higher score = better
- Recall period
- The past week
- Completion time
- About 7 minutes
- Age range
- Adults and adolescents
- Regions
- Foot & Ankle
- Conditions
- Chronic ankle instability, Lateral ankle sprain, Achilles tendinopathy, Plantar heel pain, Ankle osteoarthritis, Hallux valgus, Foot and ankle fracture, Posterior tibial tendon dysfunction
- Procedures
- Lateral ankle ligament reconstruction, Ankle arthroscopy, Achilles tendon repair, Total ankle arthroplasty, Ankle arthrodesis, Hallux valgus correction
- Languages
- English, Dutch, German, French, Spanish, Brazilian Portuguese, Persian, Turkish, Chinese, Korean, Japanese
- Test–retest (ICC)
- ADL 0.89, Sports 0.87
- Internal consistency
- Cronbach's alpha above 0.95 for both subscales
- Validity
- Content, construct and criterion validity demonstrated across a broad mix of leg, foot and ankle disorders; correlates strongly with the SF-36 physical function scale and weakly with its mental component, as expected of a region-specific functional measure.
- Responsiveness
- Both subscales discriminate patients who self-report improvement from those who do not. The Sports subscale is the more responsive of the two in athletic populations.
- Ceiling effect
- Marked ceiling effect in the ADL subscale among young athletes and patients with chronic ankle instability, many of whom score in the 90s at baseline. The Sports subscale should be the primary endpoint in that group.
- Floor effect
- The Sports subscale is frequently unscorable in older or sedentary patients, because activities they never attempt are correctly marked not applicable rather than scored zero.
Normative values
Reference values from published cohorts, for comparison against the score you calculated.
| Population | Age | Mean | SD |
|---|---|---|---|
| Uninjured control participants | — | At or close to 100% on both subscales | — |
When to use the FAAM
Well suited to
- Chronic ankle instability and recurrent lateral ankle sprain, where the Sports subscale detects the deficit that the ADL subscale misses entirely.
- Any leg, foot or ankle musculoskeletal disorder — the FAAM was validated across a deliberately heterogeneous population rather than a single diagnosis.
- Serial measurement during rehabilitation, where the published 8-point and 9-point MCIDs give a defensible change threshold.
- Clinical practice guideline recommended: the FAAM is one of the measures endorsed for ankle ligament sprain in the orthopaedic physical therapy guidelines.
Limitations and poor fits
- When a single summary number is required. There is no FAAM total, and averaging ADL with Sports produces a figure with no published interpretation.
- In young athletes if only the ADL subscale is administered — the ceiling effect will conceal real impairment.
- Where the question is specifically about the sensation of the ankle giving way, rather than difficulty with activities. The CAIT measures instability directly.
- As a diagnostic test. The FAAM quantifies self-reported function; it does not identify a lesion or establish a diagnosis.
FAAM compared with other instruments
Instruments measuring a related construct, with the practical difference between them.
| Instrument | Items | Range | What it adds |
|---|---|---|---|
| FADI | 34 | 0–100 | The Foot and Ankle Disability Index is a patient-reported questionnaire of 26 scored items — 22 activities and 4 pain items, each rated 0 to 4 for a maximum of 104 — with an optional 8-item sports subscale out of 32, where a higher score means less disability. |
| FAOS | 42 | 0–100 | The FAOS is a 42-item patient-reported questionnaire adapted from the KOOS that scores foot and ankle problems as five separate subscales — Symptoms, Pain, Activities of Daily Living, Sport and Recreation, and Quality of Life — each from 0 (extreme problems) to 100 (no problems). |
| AOFAS Ankle-Hindfoot | 9 | 0–100 | The AOFAS Ankle-Hindfoot Scale is a 100-point clinician-administered rating combining 40 points for pain, 50 for function across seven items and 10 for alignment — and although it remains the most-reported outcome in the foot and ankle literature, the society that published it withdrew its endorsement in 2011 because it was never validated. |
Copyright and permitted use
Published openly because it is the question every clinician and researcher asks before using an instrument, and almost nobody answers it.
The FAAM was published in full in the appendix of its 2005 validation paper and is distributed without charge for clinical and research use. There is no commercial licensing programme and no fee.
References
- Martin RL, Irrgang JJ, Burdett RG, Conti SF, Van Swearingen JM. Evidence of validity for the Foot and Ankle Ability Measure (FAAM). Foot & Ankle International. 2005.PMID 16309613
- Martin RL, Irrgang JJ. A survey of self-reported outcome instruments for the foot and ankle. Journal of Orthopaedic & Sports Physical Therapy. 2007.
- Carcia CR, Martin RL, Drouin JM. Validity of the Foot and Ankle Ability Measure in athletes with chronic ankle instability. Journal of Athletic Training. 2008.
- Eechaute C, Vaes P, Van Aerschot L, Asman S, Duquet W. The clinimetric qualities of patient-assessed instruments for measuring chronic ankle instability: a systematic review. BMC Musculoskeletal Disorders. 2007.doi:10.1186/1471-2474-8-6
- Martin RL, Davenport TE, Paulseth S, Wukich DK, Godges JJ. Ankle stability and movement coordination impairments: ankle ligament sprains — clinical practice guidelines. Journal of Orthopaedic & Sports Physical Therapy. 2013.
- Sierevelt IN, Zwiers R, Schats W, et al.. Measurement properties of the most commonly used Foot- and Ankle-Specific Questionnaires: the FFI, FAOS and FAAM — a systematic review. Knee Surgery, Sports Traumatology, Arthroscopy. 2018.
Editorial status
Not yet reviewedQueued for clinical review by Sam Tuffun, PT, DPT. Sign-off has not taken place — this is a placeholder assignment, not a completed review.