A new grading for easy and concise description of functional status after spinal cord lesions

Abstract

Background: Disability scales do not enable the transmission of concise, meaningful and daily function description for clinical purposes. Study design: Cross-sectional statistical analysis of 328 patients' Spinal Cord Independence Measure (SCIM) III item scores (SIS). Objective: To develop a concise and clinically interpretable data-based characterization of daily task accomplishment for patients with spinal cord lesions (SCLs). Setting: Multi-center study at 13 spinal units in 6 countries. Methods: Patients were grouped into clusters characterized by smaller differences between the patients' SIS within the clusters than between their centers, using the k-medoides algorithm. The number of clusters (k) was chosen according to the percent of SIS variation they explained and the clinical distinction between them. Results: Analysis showed that k ¼ 8 SIS clusters offer a good description of the patient population. The eight functional clusters were designated as A-H, each cluster (grade) representing a combination of task accomplishments. Higher grades were usually (but not always) associated with patients implementing more difficult tasks. Throughout rehabilitation, the patients' functional grade improved and the distribution of patients with similar functional grades within the total SCIM III score deciles remained stable. Conclusions: A new classification based on SIS clusters enables a concise description of overall functioning and task accomplishment distribution in patients with SCL. A software tool is used to identify the patients' functional grade. Findings support the stability and utility of the grades for characterizing the patients' functional status.

Validity and reliability of a locomotor stage-based functional rating scale in spinal cord injury

“…This holds also true for the 10-m walk test, the 6-min walk test and the timed up and go test. Besides these timed measures of ambulation, only SCIM, SCI-FAI, WISCI, 26 SCI-FAP and the SCIM grades 6 as categorical measures of ambulation are validated in the SCI population. The SCIM grades are constructed on a purely data-driven algorithm.…”

“…The need for a functional classification scheme based on a limited number of grades was addressed recently by the introduction of the SCIM grades. 5,6 The SCIM grades consist of eight clusters describing distinct patterns in SCIM's 17 subitems, which were derived by a purely data-driven approach (k-medoides cluster analysis). The respective grades represent rather abstract values without a direct clinical relevance and are difficult to communicate to professionals and patients.…”

Spinal cord ability ruler: an interval scale to measure volitional performance after spinal cord injury

“…Where possible, level of independence in volitional SCIM items was confined to four options as follows: complete dependence on assistance from others, partial dependence on assistance from others, independence with devices and independence without devices. These response options or scores for each SCIM item were based on literature reviews of clinically meaningful activity changes after SCI 2,3,22 and input from the working group. Thus the necessary re-scoring preserves the range found within conventional scores for individual SCIM items, but removes any misfit or disorder (i.e.…”

“…The International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI), the Functional Independence Measure (FIM) and the Spinal Cord Independence Measure (SCIM) represent commonly used ordinal scales to assess outcomes after SCI. [2][3][4][5] The total score of these multidimensional rating scales is computed by summation of the scores from individual items in the scale. However, due to the ordinal nature of each item in these scales, it is not clear to what extent a change in the total score accurately represents the overall functional capacity of an individual living with SCI.…”

“…However, due to the ordinal nature of each item in these scales, it is not clear to what extent a change in the total score accurately represents the overall functional capacity of an individual living with SCI. 3 The interval between any two values within an item may be unknown or unequal (that is, nonlinear). Furthermore, a 1-point difference in an easy item is likely not the same as a 1-point difference in another more difficult item.…”