Characteristics of the functional independence measure in traumatic spinalcord injury

Objectives: The characteristics of the Functional Independence Measure (FIM )(TM) were examined for spinal cord injury (SCI) in regard to norms over ti me by level and completeness of injury, differential benefit of motor and c ognition subscales, and "ceiling effect" after rehabilitation discharge. Design: Descriptive study of raw FIM data collected prospectively at admiss ion and discharge from acute inpatient rehabilitation, and at 1, 2, and 5 y ears after injury. Setting: National Database of the 18 Spinal Cord Injury Model Systems. Subjects: Persons with SCI, age 16 and over, with functionally complete inj uries at inpatient rehabilitation admission (ASIA grades A, B, or C), admit ted to Model System an average of 8 days after injury (standard deviation = 13, median = 1 day). Maximum sample sizes for which data were available we re: at rehabilitation admission, 3,971 cases; at discharge, 4,033; at year 1 postinjury, 903; 2 years, 712; and 5 years, 570. Outcome Measures: The FIM motor and cognition subscales. Results: There is a substantial ceiling effect of the FIM cognition items e ven by inpatient rehabilitation discharge, ie, 80% to 90% of the cases aver age 6 to 7 (independent or modified independence) across the 5 FIM cognitio n items. At 1 year 89% to 97% of cases were rated independent. FIM motor it ems were consistent with level of injury and neurologic status. Motor items (excluding locomotion items) were highly intercorrelated (correlations ran ge from .58 to .92 for self care, sphincter control, and mobility items). T rends over years 1, 2, and 5 were stable for both motor and cognition subsc ales. FIM motor gains were greatest between admission and discharge and gai ns continued through 1 year after injury, but at a much-decreased rate. Conclusions: The cognition items are not informative for detecting changes over time in SCI; at best, these items could serve as a crude cognition scr eening assessment. Motor items, in contrast, appear to reflect well the fun ctional status of individuals. High correlations among several of the motor items suggest item redundancy. FIM motor scores illustrated the improvemen ts in neurologic and ASIA scores in appropriate cases. Individuals with ASI A impairment grades of B or C at admission make the most gains in FIM motor scores. (C) 1999 by the American Congress of Rehabilitation Medicine and t he American Academy of Physical Medicine and Rehabilitation.