Functional capacity evaluation
Capacity is the damages question. It is also the one thing on this list that can be measured in pounds and minutes.
A functional capacity evaluation observes and measures what a person can actually do — lift, carry, stand, reach, tolerate — over a structured session. It is the closest thing in the file to the question a jury is actually being asked, and its predictive validity is better understood than most people assume.
What it produces
Measured performance across standardized tasks, observed consistency of effort across the session, and a statement of tolerance over time rather than a single maximum. A one-off maximum lift tells you little; a maximum that collapses over a two-hour session tells you a great deal.
Bühne and colleagues examined whether patient characteristics affect the predictive validity of functional capacity evaluation performance — the right question to ask of any test being used to forecast work capacity.
Where it is strong and where it is weak
- Strong: measured capacity on the day, observed consistency, and a direct link to the vocational question.
- Strong: it is behavioral rather than self-reported, so it is not another rating scale.
- Weak: a single session is a sample. Symptom fluctuation is real and a good report says which day it captured.
- Weak: submaximal effort lowers the result, which is why consistency measures are built in — see effort and validity testing.
- Not: a pain measurement. Capacity and pain are related and not the same.
The honest framing
A capacity evaluation that reports full effort and reduced capacity is a strong document. One that reports inconsistent effort is a problem, and it is a problem whichever side commissioned it. We do not order tests whose unfavorable results we would not report.
This practice is not aligned to a side. Its obligation runs to the patient’s health and safety, which is the same reason it is not beholden to any position that would keep it from seeing what is actually there. We do not offer opinions on liability, we do not accept a referral or a review conditioned on reaching a particular conclusion, and we will say plainly when the evidence does not support the claim — whichever party was hoping otherwise.
Common questions
Who performs the evaluation?
It is performed by trained therapists over a structured session, not in a physician visit. We interpret it against the clinical findings.
Does a bad-effort finding mean malingering?
No. Inconsistent effort has many causes including fear of re-injury, deconditioning and pain itself. It is a finding to explain, not a verdict.
Is one session enough?
It is a sample. Where fluctuation is central to the claim, that limitation should be stated in the report rather than argued about later.
Does capacity testing establish causation?
No. It measures current function — see causation and apportionment.
Related reading
- Effort and validity testing
- Objective corroboration
- Future care and life-care plans
- The chronic pain epidemic
- Records that survive cross
Ask whether capacity testing is the right question
If the dispute is about work, it usually is. If the dispute is about causation, it is not.
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Monday to Friday, 8:00 a.m. to 5:00 p.m. Nothing on this page is legal advice, and nothing on it is medical advice.
Sources
- Bühne D et al. Do patient characteristics affect the predictive validity of functional capacity evaluation performance? International Archives of Occupational and Environmental Health, 2022. PubMed 34709439
- Johnson-Greene D et al. Relationship between performance validity testing, disability status, and somatic complaints. The Clinical Neuropsychologist, 2013. PubMed 23121595
- Rikard SM et al. Chronic pain among adults — United States, 2019–2021. MMWR, 2023. PubMed 37053114
- Raja SN et al. The revised International Association for the Study of Pain definition of pain: concepts, challenges, and compromises. Pain, 2020. PubMed 32694387