Adaptation and psychometric validation of the Kannada Version of the Vanderbilt Fatigue Scale: a tool for effective assessment of listening-related fatigue

The Vanderbilt Fatigue Scale (VFS-A) is a self-reported scale for assessing listening-related fatigue among adults with hearing loss and communication-related difficulties. This study aims to translate the VFS-A into Kannada and validate it among the Indian population. The original version of the VFS-A was translated and culturally adapted into Kannada according to widely accepted guidelines for cross-cultural adaptation of scales for different languages. This involved forward translation, backward translation, critical assessment by an expert panel, cognitive debriefing, and validation measures. In the validation phase, the VFS-A was administered to 276 participants with hearing loss, along with a standard hearing assessment. The Fatigue Severity Scale (FSS) was used to assess convergent validity. The VFS-A has high internal consistency (Cronbach's alpha = 0.976) across items and sub-domains. An exploratory factor analysis revealed that the Kannada version of VFS-A data was satisfactorily fit, assuming a unidimensional factor model structure. Assessment of associations between FSS and VFS-A scores revealed a moderate positive correlation (r = 0.422; p = 0.001), suggesting good convergent validity. The Kannada version of the VFS-A is a psychometrically valid tool for assessing listening-related fatigue that may be useful for clinical and research purposes.