Additional Evaluative Tools for Multiple Sclerosis
Additional tools are available to measure disease activity. These are used mainly in clinical trials to help evaluate disease progression as well as changes in specific symptoms, such as fatigue, strength, mobility, vision, cognition, and others.
Through these universally accepted systems of measurement, physicians can record their patients’ presenting condition and subsequent improvements, relapses, or disease progression. These systems are particularly valuable in clinical trials, which test the effectiveness and safety of experimental treatments for MS, prior to their approval by the United States Food and Drug Administration (FDA).
The most widely known scale among the MS community is the Kurtzke Expanded Disability Status Scale (EDSS). Dr. Kurtzke first introduced this system in 1955 as the Disability Status Scale (DSS). It used whole numbers from one to 10 to measure degree of disability, largely in terms of mobility.
To make the measurements more sensitive, Kurtzke later “expanded” the scale by adding half-points between the numbers. The EDSS is used in conjunction with Kurtzke’s Functional System (FS). This measures the function of seven major systems in the CNS (plus a section for “other”), each relating to the different areas of functioning that can be affected by MS (such as movement, sensory, bowel and bladder, vision, cognition, etc.). These are each graded on a scale of zero (normal) to six (severe).
A newer measurement system designed to be even more sensitive is the MS Functional Composite (MSFC) scale. This measures lower extremity function with a Timed 25-Foot Walk, upper extremity function through the 9-Hole Peg Test (9-HPT), and cognitive function, using the Paced Auditory Serial Additions Test (PASAT).