What Is the Multiple Sclerosis Functional Composite?

The Multiple Sclerosis Functional Composite (MSFC) is a standardized, three-part tool used to assess the degree of disability in patients with MS. The MSFC was created for use in clinical studies and measures three key areas of MS disability—leg function/walking, arm and hand function, and cognitive function.

This article will review these three components and discuss how the MSFC is administered and scored.

Components of the MSFC

Developed by the National MS Society (NMSS) Clinical Outcomes Assessment Task Force in 1994, the MSFC reflects the progression of neurological disability through the following three separate tests.

Timed 25-Foot Walk (T25W)

The T25W measures leg function and walking.

During the T25W, the patient is asked to walk 25 feet as fast as possible (called Trial 1). The patient is then immediately asked to walk back to the starting point (called Trial 2). A five-minute rest period after Trial 1 is allowed, and a walking assistive device, such as a cane or walker, can be used during the test.

The test is discontinued if the patient cannot complete Trial 1 or Trial 2 in 180 seconds.

9-Hole Peg Test (9HPT)

9HPT measures arm and hand function.

During the 9HPT, while sitting, the patient is asked to place pegs one by one into nine separate holes arranged in a board placed on a table. Next, the patient is asked to remove the pegs. Each hand is tested twice.

The amount of time it takes for the patient to place and remove all nine pegs is recorded for each trial. The test is discontinued if the patient cannot complete the test in five minutes.

Paced Auditory Serial Addition Test (PASAT-3)

The PASAT-3 measures cognitive function, specifically information processing and speed, working memory, and attention.

During the PASAT-3, a series of numbers are presented by an audiotape or compact disc (CD) player every three seconds. The patient is asked to add up the numbers, and the number of correct answers is recorded.

Up to three practice trials with a set of 10 numbers are allowed prior to the actual test. The test is discontinued if the patient does not get at least two answers correct (consecutive or not) on any one of the three practice trials.

MSFC Administration

The MSFC is administered by a trained examiner, typically a neurologist (medical doctor specializing in conditions of the brain and nervous system), nurse, medical assistant, or healthcare technician. Administration time for all three measures is approximately 20–30 minutes.

At the start of MSFC, the examiner states the instructions exactly as they appear in the MSFC manual. Translations of the instructions are available in several languages, including French, German, Dutch, Greek, and Hebrew.

The MSFC examiner is trained to be friendly and approachable but also professional and objective. This means that they cannot share any feedback or information about the patient's performance on the tests.

Since the entire process can be a bit challenging and extremely trying on the nerves, the examiner is trained to help the patient maintain physical and emotional comfort during all three tests.

The testing space for the MSFC is typically a separate, designated room; although, the Timed 25-Foot Walk test may be performed in a public hallway.

To minimize any distractions, only the patient and the examiner are present in the testing area. Cell phones, pagers, and watches are turned off, and the room is kept clear of any obstacles or unnecessary materials. A "Do Not Disturb" sign is usually placed on the door when testing is in progress.

How an MSFC Score Is Calculated

The MSFC score is made by converting the scores for each component/test into a Z-score. If tests cannot be completed due to disability or fatigue, a certain score (not necessarily zero) is given based on MSFC instructions.

The Z-scores, which are calculated from standardized formulas, are then averaged to create an overall composite score.

Composite scores can be compared among treatment and control groups in MS clinical trials to assess the benefit of certain clinical interventions, such as taking disease-modifying antirheumatic drugs (DMARDs). They may also be analyzed over time to assess individual disability improvement or worsening.

Besides the composite score, the three individual scores are also usually examined. This is because a patient may experience worsening disability in one area like walking over time but improvement in another area like cognition (mental processes by which knowledge and comprehension are ained).

As such, a patient's overall MSFC score could remain stable since their scores in the three areas average out, even though their functioning in one area is deteriorating.

Summary

The MSFC is a three-part tool used in clinical studies to measure disability progression in patients with MS. It includes the assessment of leg function, arm and hand function, and cognitive function. Scores from each of the three components are converted into Z-scores and averaged to create an overall composite score.

A Word From Verywell

Scientific evidence consistently suggests that the MSFC is a suitable and valid tool for evaluating the degree of impairment in patients with MS. Of course, as with any research tool, the MSFC does have some drawbacks—for example, it does not address problems associated with vision, sensory, bladder, bowel, or sexual function.  

Regardless, gaining basic knowledge about the MSFC is a reasonable and empowering strategy. Your neurologist may bring it up during an appointment, or you may encounter it one day if you or a loved one decide to participate in an MS clinical trial.