Cross-cultural adaptation and validation of the Arabic Rating-of-Fatigue scale

Abstract

Background The Rating-of-Fatigue (ROF) scale is increasingly used to quantify subjective sensations of fatigue in exercise science. However, despite its growing international use, its psychometric properties have not yet been examined in Arabic-speaking populations. This study aimed to translate the ROF into Arabic and evaluate its content validity, face validity, and construct validity relative to perceived exertion and heart rate (HR) responses during graded exercise and subsequent passive recovery.

Methods The study was conducted in Tunisia and followed established international best-practice guidelines for cross-cultural adaptation. The ROF and its instructions were forward-translated, synthesized, and back-translated using blinded translators, with linguistic and conceptual equivalence evaluated using Sperber’s framework and expert committee review. Face validity was assessed in 68 Arabic-speaking adults. Construct validity was examined in 43 adult participants during a modified Bruce treadmill test followed by 10 min of seated recovery, with the Arabic Rating-of-Fatigue scale (ROF-Ar), Borg CR10, and HR recorded at each exercise stage and during recovery. Within-participant correlations were pooled using Fisher’s r-to-z transformation.

Results Sperber-based ratings indicated high linguistic and conceptual equivalence between the ROF-Ar and the original scale, with no item exceeding the predefined revision threshold. Face validity findings showed that participants predominantly interpreted the ROF-Ar as a measure of fatigue rather than exertion and that standardized instructions improved descriptor-related comprehensibility and reduced perceived difficulty. During graded exercise, ROF-Ar demonstrated very strong pooled correlations with Borg CR10 (r = 0.94; 95% CI 0.92–0.95; p < 0.001) and HR (r = 0.95; 95% CI 0.93–0.96; p < 0.001). During recovery, the association between ROF-Ar and Borg CR10 attenuated substantially (r = 0.35; 95% CI 0.15–0.52; p < 0.001), whereas the association with HR remained moderate (r = 0.63; 95% CI 0.49–0.74; p < 0.001).

Conclusions The Arabic version of the ROF demonstrated high linguistic and conceptual equivalence, adequate face validity, and strong construct validity. The recovery-phase dissociation between perceived fatigue and perceived exertion supports the intended conceptual distinction of the ROF and justifies the use of ROF-Ar for assessing subjective fatigue during exercise and recovery in Arabic-speaking research and applied settings.