Physical Fatigue Assessment, Linguistic Adaptation, and Validation of Fatigue Severity Scale among Type 2 Diabetes Mellitus Population

Abstract

Objective

The objective of this study was to conduct a cross-cultural adaptation of the Fatigue Severity Scale (FSS) from English to Kannada and to evaluate the content validity and reliability of the Kannada version among individuals with type 2 diabetes mellitus.

Methods

This study was conducted in 2 phases. In phase 1, the original English version of the FSS was translated into Kannada using the forward–backward translation method to maintain conceptual equivalence. The preliminary Kannada version was reviewed by 5 healthcare professionals for clarity, cultural relevance, and content comprehensiveness. In phase 2, the final Kannada version (FSS-K) was administered to 80 individuals with type 2 diabetes mellitus, aged between 30 and 70 years, all with a disease duration of more than 10 years. Descriptive statistics were used to summarize demographic details. Internal consistency of the FSS-K was evaluated using Cronbach’s alpha. Test-retest reliability was assessed using the Intraclass Correlation Coefficient (ICC), and inter-item correlation was determined using Pearson’s correlation coefficient. One-way ANOVA was conducted to compare FSS scores across different subgroups, including gender, age, sleep duration, and clinical conditions.

Results

The internal consistency of the Kannada version was high, with a Cronbach’s alpha of 0.952. The test-retest reliability showed excellent agreement with an ICC of 0.999. A strong correlation was observed between pre-test and post-test scores of the Kannada FSS, indicating robust reliability.

Conclusion

This study showed that the Kannada version of the Fatigue Severity Scale is a valid and reliable tool for assessing fatigue in individuals with type 2 diabetes mellitus.