Reliability and validity of the Spanish adaptation of the Functional Independence Measure + Functional Assessment Measure

BACKGROUND: The Functional Independence Measure + Functional Assessment Measure (FIM+FAM) Scale is one of the most widely used instruments to measure functional independence post-stroke, and features many cultural adaptations to various languages. AIM: The aim of this study was to determine the psychometric properties of a Spanish cross-cultural adaptation of the FIM+FAM for use in the stroke population. DESIGN: Observational study. SETTING: Outpatient long-term service of a neurorehabilitation unit. POPULATION: One hundred and twenty-two individuals with stroke. METHODS: The functional independence of the participants was assessed with the adapted version of the FIM+FAM. Additionally, the functional, motor and cognitive condition of the participants was assessed with a battery of standardized clinical instruments. Finally, a group of 31 participants out of the total were evaluated a second time with the FIM+FAM by a different evaluator than the one who performed the first evaluation. Internal consistency, inter-rater reliability and convergent validity with other clinical instruments of the adapted version of the FIM+FAM were determined. RESULTS: The internal consistency of the adapted version of the FIM+FAM was excellent, as evidenced by Cronbach’s α values that exceeded 0.973. The inter-rater reliability was likewise excellent, with correlations above 0.990 in all domains and subscales. Additionally, the convergent validity of the scale adaptation with clinical instruments was variable, with values ranging from 0.264 to 0.983, but consistent with the construct assessed in the different instruments examined. CONCLUSIONS: The internal consistency, inter-rater reliability and convergent validity of the Spanish-adapted version of the FIM+FAM Scale showed excellent reliability and validity of the adaptation, which supports its use to assess functional independence after stroke. CLINICAL REHABILITATION IMPACT: Availability of a valid adaptation for the evaluation of functional independence after stroke in Spanish population.