Reliability and validity of a self-report FIMTM(FIM-SR) in persons with amputation or spinal cord injury and chronic pain

Objective: To evaluate the reliability and validity of a self-report FIM(TM) (FIM-SR) in two samples of adults with disabilities. Design: Participants in a clinical trial of amitriptyline for pain (n = 84 with spinal cord injury [SCI], n = 38 with amputation) provided responses to the study measures via telephone interview. Reliability was estimated using Cronbach's alpha and test-retest correlation coefficients, and validity was examined by comparing FIM-SR scores with the Craig Handicap Assessment and Reporting Technique (CHART) by comparing the CHART scores between the participants with SCI and amputation, and by comparing CHART scores between subjects with different levels of SCI. Results: In the SCI sample, the FIM-SR demonstrated adequate reliability, and correlational analyses supported the validity of the FIM-SR motor scales. In addition, the FIM-SR motor scales discriminated subjects with different diagnoses (SCI vs. amputation) and injury levels (paraplegia vs. tetraplegia). The psychometric properties of the entire FIM-SR in the amputation sample and of the FIM-SR cognitive scales in the SCI sample were difficult to determine due to a ceiling effect in which these scale scores were skewed toward the top end of the range. Conclusions: The FIM-SR motor scales and total FIM-SR score are reliable and valid measures of perceived functional independence in individuals with SCI. However, all of the FIM-SR scales in the amputation sample, and the FIM-SR cognitive scales in the SCI sample, seem to be less useful measures of functioning due to subjects reporting high levels of independence. The FIM-SR should be retested in amputation samples with more variable levels of functioning.