Activities-specific balance confidence scale: a Rasch evaluation of the Arabic version in lower-limb prosthetic users

Abstract

PurposeTo evaluate the psychometric properties of the Arabic version of the Activities-Specific Balance Confidence Scale using the 5-option response categories for individuals with lower limb amputation (ABC-5/Ar).Materials and methodsThis was a methodological study on a convenience sample of individuals with unilateral lower-limb amputation attending outpatient rehabilitation centres in Saudi Arabia and Turkey (N = 155). Rasch analysis (WINSTEPS version 4.6.5) was used to examine the 5-categories rating scale structure, item fit, item difficulty hierarchy, person separation index, unidimensionality, local item dependency, and differential item functioning.ResultsThe ABC-5/Ar 5-response option demonstrated an appropriate model fit. Most items fit the Rasch model, except for item #12 walk in a crowded mall, which showed an overfitting value of 0.63. The person separation indices 2.95 (Cronbach's alpha = 0.96). Principal component analysis of residuals confirmed the unidimensionality of the scale; however, local dependency was detected between item #14 Ride in escalator holding rail, and item #15 Ride in escalator not holding rail.ConclusionsThe findings suggest that the ABC-5/Ar shows promise in assessing balance confidence in Arabic-speaking lower-limb prosthesis users. However, further studies with larger sample sizes and in diverse clinical contexts are needed to confirm its effectiveness in various clinical settings. Overall, our Rasch-based study provides additional evidence to support the psychometric appropriateness of using the Activity-specific Balance Confidence scale with the 5-category options (ABC-5) of the Arabic version among lower prosthesis users.Clinicians and researchers should be mindful of cultural and contextual differences that exist among Arabic-speaking population which may influence how participants responded to certain items in the scale.It is essential to conduct a comprehensive psychometric evaluation to guide the implementation and interpretation of scales, particularly in Arabic-speaking countries due to the scarcity of validated and standardised outcome measures to assess prosthesis users' confidence