The Persian Version of the SIGAM Mobility Scale Was Cross-Culturally Adapted and Validated in Adults with Lower Limb Amputation

Abstract

Background: Mobility assessment is a crucial aspect of rehabilitation for individuals with lower limb amputation, as it directly influences their independence and quality of life. The objective of this study was to translate and cross-culturally adapt the Special Interest Group in Amputee Medicine (SIGAM) mobility grades questionnaire in the Persian language and to investigate its psychometric properties. Methods: The SIGAM mobility scale was translated into Persian according to international guidelines for cross-cultural adaptation of self-reported measures and was administered to forty Persian-speaking people with lower limb amputations. Measurement properties were evaluated following COSMIN (COnsensus-based Standards for the Selection of Health Measurement INstruments) recommendations and included internal consistency, test-retest reliability, and hypotheses testing for construct validity by comparing SIGAM mobility grades to the Locomotor Capabilities Index-5 (LCI-5), Houghton scale, Activities-specific Balance Confidence (ABC) scale, the 2-Minute Walk Test (2-MWT), and the Timed Up and Go (TUG). Results: SIGAM mobility scale demonstrated acceptable internal consistency (Kuder-Richardson 20 coefficient = 0.72) and excellent test-retest reliability (Cohen Kappa coefficient = 0.85). Hypothesis testing for construct validity confirmed the good to very good correlations of the Persian SIGAM mobility scale with the LCI-5 (r = 0.63, 0.55, and 0.63 for the general, basic, and advanced activities components, respectively), Houghton scale (r = 0.63), ABC scale (r = 0.73), 2-MWT (r = 0.50), and TUG test (r = -0.51). Conclusion: The Persian version of the SIGAM mobility scale demonstrated preliminary evidence of acceptable psychometric properties, supporting its clinical applicability.