A PROPOSAL FOR A UNIFORM MINIMAL RECORD OF DISABILITY IN MULTIPLE SCLEROSIS

Abstract

Rating schemes in multiple sclerosis (MS) have followed two separate pathways. One grouping is designed to define the nature and severity of the specific neurologic deficits found in MS, and may be looked upon as attempts to quantitate a standard neurologic examination. The other grouping is designed to measure end-organ impairment regardless of cause and nature, and they arise primarily from physiatrists. I believe each grouping must remain separate. One system in moderate usage for the neurologic impairment in MS is that consisting of eight Functional Systems (FS) plus an overall Disability Status Scale (DSS) which is based on the Functional Systems. The FS are Pyramidal, Cerebellar, Brain Stem, Sensory, Bowel & Bladder, Visual or Optic, Cerebral or Mental, and Other or Miscellaneous Functions. The last is a “yes-no” category, but all other FS have designated grades from O (normal) to 5 or 6 (maximal impairment). The eight FS though, taken as normal (O) or impaired (1) together provide a binary description of the pattern of involvement in MS. Over half the MS patients in one series fell within one of only 14 of the 256 possible patterns, and 1/4 had one of but four patterns. Approximate FS equivalents are provided for each step of the DSS, which ranges from O (normal) to 10 (death due to MS); the DSS itself can be treated as a true arithmetical rather than a rank-order (ordinal) scale. For the second grouping of rating systems, a scale for consideration as a uniform minimal record of disability is proposed, based largely upon several scales adapted by Carl Granger. This scale, called the Incapacity Scale, consists in its minimal version of 11 items: Stair climbing; Ambulation; Chair/bed transfer; Bowel function; Bladder function; Bathing; Dressing; Grooming; Feeding; Communication, and Physical problems. Other variants of the basic Scale are presented, formed by inclusion of Toilet transfer and/or Societal role. At the 1980 Stockholm meeting on MS disability it was urged that Communication be separated into Vision plus Speech & Hearing, and that two additional items of Fatigability and Psychic function be added. This then provides a full scale of 16 items, which is proposed as the preferred version of the Incapacity Scale. Each item on each variant of the Scale is scored on a O to 4 basis. O is normal function; 1 is impairment present but able to perform without aid; 2 is impairment present but able to perform with mechanical assistance; 3 is able to perform with human assistance or by substitution for the function; 4 is loss of the function without effective substitution. Those general rules are modified for several functions because of their nature. As a first approximation, the total Incapacity Scale score is taken as the sum of the unweighted scores for each item. The Incapacity Scale in its original 13-item form was scored readily by Carl Granger for a group of 39 patients with MS who had been assessed according to his own scales. Correlation of total scores for the 11- and 13-item forms of the Incapacity Scale with those for Granger' own four systems was high, with co-efficicnts of correlation of 0.76 to 0.94. This simple system may therefore meet the requirements for a minimal record of disability that could be applied easily and uniformly in many clinical settings.