Why Cognitive Test Scores Don't Always Tell Us About Work Capacity

Understanding the role of Cognitive Functional Capacity Evaluations in return-to-work planning

A person can perform well on a cognitive screening test and still have difficulty managing the demands of their job.

For example, an employee may have no obvious difficulty remembering instructions or completing individual tasks but struggle when several things require attention at once. Interruptions, competing priorities and the need to work accurately under time pressure can reveal difficulties that are not always apparent during conventional cognitive testing.

This presents a challenge when determining someone's readiness to return to work. Cognitive test scores provide useful information, but how well do they reflect the person's ability to manage their actual job duties?

Looking Beyond Cognitive Test Scores

Traditional cognitive assessments provide valuable information about abilities such as attention, memory, processing speed and executive functioning. They can help identify cognitive difficulties and determine whether further assessment is needed.

However, most jobs rarely require these abilities in isolation.

Consider an administrative professional responsible for scheduling appointments, responding to emails, answering phone calls, completing documentation and handling unexpected requests.

The individual may be capable of completing each activity separately. However, difficulties may appear when several demands compete for attention, interruptions occur or priorities change throughout the day.

Successful performance requires the individual to organize information, keep track of unfinished tasks, recognize errors and determine what needs to be done next.

These abilities involve executive functioning—the cognitive processes that allow us to plan, organize, monitor and adjust our behaviour to complete tasks.

Although conventional cognitive testing can identify difficulties in these areas, observing someone perform complex activities may provide additional information about how those difficulties affect everyday functioning.

What Does a Cognitive Functional Capacity Evaluation Involve?

A Cognitive Functional Capacity Evaluation (Cog FCE) assesses how an individual's cognitive abilities affect their performance during functional activities, especially those related to work.

Depending on the referral questions, an occupational therapist may combine standardized cognitive assessments with performance-based tasks that examine abilities such as planning, organization, attention, problem-solving, processing speed and multitasking.

Some assessments involve everyday activities, such as organizing a calendar or following a series of instructions. Others may involve simulations of specific job duties.

An important part of the evaluation is observing how the individual approaches and completes the activity, rather than focusing exclusively on the final score.

For example, does the person recognize when they have made a mistake? Are they able to correct it independently? Do they develop an effective strategy, or do they lose track of the task when additional tasks are introduced?

Another important consideration is the level of independence demonstrated.

Two individuals may complete the same activity with similar results, but one may organize the task efficiently and recognize errors independently, while the other requires repeated instructions, prompting or redirection.

These differences can be important when considering the cognitive demands of independent work.

Not every Cog FCE uses the same testing battery. The tests selected should reflect the individual's reported difficulties, medical information, occupational demands and the specific questions the evaluation is intended to address.

What Does the Research Tell Us?

Recent research has examined the role of performance-based assessments in understanding functional cognition.

In 2025, Lee and colleagues published two systematic reviews in the American Journal of Occupational Therapy. The first identified 25 performance-based assessments of functional cognition, while the second evaluated research concerning their measurement properties, including validity and reliability.

The reviews found evidence supporting certain assessments but also identified gaps in the available research. Further investigation is needed into the reliability and other properties of many measures.

A 2026 review by Schwab and colleagues examined Functional Capacity Evaluations in medico-legal settings. The authors emphasized the importance of standardized assessment methods, consideration of individual and contextual factors, and relating assessment findings to occupational demands.

Although this review examined FCEs more generally rather than Cognitive FCEs specifically, its recommendations are relevant to the assessment of cognitive work capacity.

Together, these publications support the use of carefully selected performance-based measures as part of a wider assessment, while also highlighting important limitations.

For example, performing well during a structured assessment does not necessarily establish that an individual can sustain comparable performance throughout a full workday or over consecutive days. Similarly, research supporting an individual cognitive assessment does not automatically establish the validity of an entire Cog FCE testing battery.

These are important considerations when interpreting results and developing return-to-work recommendations.

Why Job Demands Matter

Cognitive demands can differ substantially between occupations, even when the work environments appear similar.

An accountant, dispatcher and administrative assistant may all spend much of their workday at a computer. However, their responsibilities can involve very different levels of complexity, time pressure, interruptions and decision-making.

An accountant may need to maintain accuracy while reviewing detailed financial information. A dispatcher may be required to rapidly prioritize competing requests, while an administrative employee may need to manage several ongoing tasks and respond to frequent interruptions.

For this reason, identifying a cognitive impairment is only part of determining its potential impact on work capacity.

The assessment must also consider how the individual's demonstrated abilities and difficulties relate to the requirements of their job.

Where detailed occupational information is available, Cog FCE findings can be compared with the cognitive demands of a specific position. This may help identify duties the individual can manage independently, activities that present difficulties, and areas where workplace modifications may be appropriate.

When adequate job-demand information is unavailable, conclusions about the individual's suitability for a particular position are more difficult to determine.

Cognitive Fatigue and Work Endurance

Another consideration is whether cognitive performance changes over time.

An individual may complete a short task accurately but experience increasing difficulty with attention, processing speed or organization during more prolonged or demanding activities.

This may be especially relevant following an acquired brain injury or other neurological condition where cognitive fatigue is a concern.

During a Cog FCE, the occupational therapist may monitor reported fatigue and observe changes in task accuracy, completion time, attention and strategy use throughout the assessment.

However, these observations have limitations.

Completing several hours of cognitive assessment does not necessarily demonstrate the ability to maintain comparable performance throughout an eight-hour workday or across consecutive workdays.

The duration of testing, the demands of the activities performed, the individual's reported symptoms and their recovery following activity all need to be considered when interpreting cognitive endurance.

Putting the Findings Into Context

A Cognitive FCE is not intended to provide a simple pass-or-fail determination of someone's ability to work.

Rather, it can help identify the cognitive demands an individual is able to manage, where difficulties arise, and whether workplace modifications or additional rehabilitation may be appropriate.

Depending on the findings, recommendations may address workload, task complexity, environmental distractions, organizational supports, scheduled breaks or a graduated return-to-work plan.

The results must also be considered alongside medical information, reported symptoms, work history and the actual requirements of the job.

Cognitive testing tells us something about a person's abilities. Observing how those abilities are used during functional activities adds another piece of the picture.

About Benchmark Occupational Therapy

Benchmark Occupational Therapy is a Winnipeg-based occupational therapy practice providing Physical and Cognitive Functional Capacity Evaluations, Job Demands Analyses and other functional and workplace assessments.

For more information about Cognitive Functional Capacity Evaluations or to discuss a referral, please visit our Cognitive FCE services page or contact Benchmark Occupational Therapy.

References

Lee, Y., et al. (2025). Performance-based assessments of functional cognition in adults, Part 1—Assessment characteristics: A systematic review. American Journal of Occupational Therapy, 79(4). https://doi.org/10.5014/ajot.2025.050948

Lee, Y., et al. (2025). Performance-based assessments of functional cognition in adults, Part 2—Psychometric properties: A systematic review. American Journal of Occupational Therapy, 79(4). https://doi.org/10.5014/ajot.2025.050949

Schwab, L., Van de Velde, D., Braeckman, L., & De Baets, S. (2026). Functional capacity evaluations in medico-legal contexts: A scoping review of best practices, limitations, and areas for improvement. Frontiers in Rehabilitation Sciences, 7, 1777330. https://doi.org/10.3389/fresc.2026.1777330