One of the greatest challenges with functional capacity evaluations (FCEs) is the measure of its validity. In addition to the actual test, the validity of the FCE is influenced by the evaluator's intended use, interpretations of the results, and decisions made on those interpretations.

Most of the time, FCEs are used on a one-time basis and without sufficient corroborative findings to determine a previously injured person's capacity for safe return to work or a healthy person's transition to a new job.

The Strength of the Test

Valid uses of FCEs are as a screening tool to assist in the decision-making process as to what happens next in an injured worker's rehabilitation and return to work, or as part of a worker's initial evaluation for or discharge summary from a work-hardening program. FCEs can also be used to add information or corroborate information obtained in a postoffer screen, a tool used by some companies to predict a new-hire's capacity to do a job. Sometimes the new-hire realizes during a postoffer screen that he cannot or would not want to do that job. He then may choose to not take the job; and it saves the company from a potential claim, and the new-hire is spared a potential injury.

FCEs can be purchased or designed in the clinic. They may use expensive mechanical devices interfaced with computers; or handmade boxes, crates, and push/pull sleds. The evaluator's knowledge and skill are additional variables to consider in good and not-so-good practices with FCEs. Generally, a licensed occupational or physical therapist administers the FCE to the worker. Unfortunately, there are other professionals using these tools who are not academically or clinically educated in biomechanical and psychosocial function and dysfunction.

These evaluations may be administered in 1 or 2 days and, on average, last from 2 to 4 hours. Aspects of an FCE vary and may include an interview, a therapeutic physical examination, material-handling and nonmaterial-handling capabilities, and observations. During the interview, the therapist gathers information about the worker's injury, course of therapy, current pain reports, and general functional status. Information about the worker's job-related duties and demands is also solicited. The therapist may also be assessing nonmaterial-handling capacities, such as sitting or standing tolerance during the interview process. A physical examination of posture, range of motion, strength, flexibility, and cardiovascular conditioning may follow.

The worker is then put through a series of material-handling tasks, such as lifting incrementally increasing weights at different heights, during which the worker reports pain levels and the therapist observes pain behaviors and body mechanics. Finally, the therapist, or software program, generates an assessment of capacity for return to work or transition into new employment—based on the objective findings and the clinician's judgments.

Limitations

An FCE cannot predict a person's capacity to work for 8 to 10 hours per day, 4 to 6 days per week, 52 weeks per year. At best, the FCE may simulate certain skills and capacities needed to perform the job. But the demands on the musculoskeletal system differ for various tasks and may result in different levels of strain, symptoms, and potential for reinjury.

An FCE cannot capture the skills and capacities needed to perform essential job duties or those that are critical relative to the worker's injury and presenting symptoms. At best, the client is observed for up to an hour performing one nonmaterial-handling task, typically sitting. It may be concluded that the client can sit "continuously for up to 1 hour." As such, the following return-to-work scenario is possible: The worker sits for an hour continuously with a 2-minute break, only to return to sit for another hour, and then another and another; the complaints begin after a few days followed by a sick day or two.

Unfortunately, I have also witnessed therapists confuse abilities by inferring that the ability to lift 25 pounds equates to the ability to perform sedentary work. What if the worker has discogenic pain and it is sitting, not lifting or standing, that aggravates the symptoms most? In fact, sitting postures can produce more compressive forces on the lumbar disks than standing and even lifting in some cases. And let's not forget the environment. Musculoskeletal fatigue will be hastened if the person happens to work in extreme cold or hot conditions. Are these environmental factors simulated during an FCE? Is a projected performance reliable or valid?

Further Options

If we should not rely solely on the results of an FCE, what are better options for predicting a person's safe return to work? An authentic assessment would be a more valid option. Authentic assessment is a test, activity, or set of activities that most closely resemble reality. In the case of injured workers, the reality we want to simulate is their work, including tasks, tools, and environment. The best option then is to provide therapy on the job. The therapist can grade the work activities, in duration, forces, and performance rates, as needed until the worker can safely return to full capacity. In the meantime, the worker is educated on proper body mechanics and tasks, or sometimes the workstation can be modified to minimize risk factors.

The next best option is to have the injured worker participate in a work-hardening program. Although this program takes place in a clinic, critical work tasks can be simulated extremely well. Additionally, conditioning is a major component of work-hardening programs, and can be especially important for the worker who has deconditioned during the acute phases of rehabilitation and must return to a moderately heavy job.

There is pressure today to create briefer and more cost-effective FCEs. Are we curbing direct and indirect costs by investing in a process that has such questionable reliability and validity? FCEs are not bad in and of themselves, but they can be used poorly. Use them as only a piece of the puzzle. FCEs should be used cautiously, to supplement the results of diagnostic testing, surgical reports, physical examinations, job-site analyses, therapeutic interventions, and personal testimony in determining a worker's potential for safe return to work. In fact, when it comes down to it, the ultimate test awaits the rehabilitated worker once he returns to his job.

Mary Reiner, PT, OTR/L, has more than 10 years of experience in evaluating patients in return-to-work programs. Reiner is currently a traveling therapist based in Cincinnati. For more information, contact .