Disability Ratings in IMEs, Peer Reviews, and Functional Capacity Exams

Welcome back to our 26 in '26 Blog Series. Each post will address a top-of-mind topic in the clinical evaluation services sector. The previous post in the series covered Causation. This is the fourth post in our series and discusses Disability.

Few elements of a claim generate as much disagreement as disability ratings—because “disability” is not a single concept. It can mean medical impairment, functional limitation, work capacity, or loss of earning ability, depending on the jurisdiction, line of coverage, and purpose of the evaluation.

Impairment refers to a medical condition or loss of bodily function, often expressed using standardized systems such as the AMA Guides. Disability reflects how impairment affects the ability to perform work or activities and is often defined by statute, policy language, or jurisdictional rules. Function addresses what a person can do safely and consistently, regardless of diagnosis or impairment rating.

Standards matter. A defensible rating requires applying the correct standard (e.g., AMA Guides edition, jurisdictional impairment schedule, policy definitions), supporting conclusions with clear clinical evidence, and explaining methodology. Common breakdowns occur when the wrong standard is applied, the method is not described, or apportionment is asserted without a rationale.

Functional Capacity Exams (FCE) can provide an objective measure of physical tolerance, consistency, and capacity. But FCEs are not disability determinations. They contribute data that must be integrated into a medical and coverage-specific framework. Treating FCE results as a stand-alone basis for a disability decision is a frequent source of dispute.

Fitness-for-Duty Exams (FFD) intersect with disability but are not disability determinations. FFD focuses on safety and capability relative to essential job duties, particularly for safety-sensitive roles. An individual may be impaired yet fit for duty with accommodations, or medically stable yet not fit for a specific safety-sensitive position.

Peer Reviews evaluate whether ratings and restrictions follow applicable standards, whether functional conclusions align with evidence, and whether FCE findings are appropriately interpreted. When roles are clear and methodology is traceable from findings to conclusions, disability disputes become more resolvable.

Best Practice
Make ratings traceable: require the correct governing standard, clear methodology, evidence linkage, and—when relevant—supported apportionment. Integrate functional data without asking FCEs to “decide disability.”

Next in the Series
Next: E — Examiner Selection: why fit matters more than speed for defensible outcomes.