The validity in persons with spinal cord injury of a self-reported functional measure derived from the functional independence measure

Study Design. A cross-sectional, mailed survey on impairment and function using 6361 respondents to the Spinal Cord Dysfunction National Veterans Survey who reported spinal cord injury as the sole cause of their spinal cord dysfunction. Objectives. To establish the concurrent and construct validities of a Self-Reported Functional Measure appropriate for use in patients with spinal cord injuries. Summary of Background Data. Functional assessment is of increasing importance in clinical care, quality assurance, and national health-care planning. There is a conspicuous need for validated functional assessment measures that are rapid, reliable, and appropriate for use in the disabled population. Methods. The correlation was examined of hours of personal assistance, number of affected limbs, amount of motor impairment, and amount of combined limb-motor impairment to Self-Reported Functional Measure response tertile (scores, 13-32, 33-45, 46-52; lower scores indicated worse function). Results: There were statistically significant correlations between Self-Reported Functional Measure score and hours of personal assistance (P < 0.001), the number of affected limbs (P < 0.001), the amount of motor impairment (P < 0.001), and the amount of combined limb-motor impairment (P < 0.001). For example, 87% of people with the most limb-motor impairment (four affected limbs and no useful movement) were in the lowest Self-reported Functional Measure tertile, compared with 3% of people in the least-affected category of limb-motor impairment. Furthermore, visual, sensory, or memory impairment did not influence the correlation between limb-motor impairment and Self-Reported Functional Measure score. Conclusions. The Self-Reported Functional Measure shows good concurrent and construct validities.