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Original Research (Preprint)

Vol. 1 No. 2 (2025): Regular Issue

Psychometric properties of the Mongolian version of the Chalder Fatigue Scale

  • Uuriintuya Batmend
  • Uyanga Angarag
  • Naidan Bat-Ulzii
  • Binderiya Bayanmunkh
  • Gantsetseg Tumur-Ochir
  • Tsolmon Jadamba
  • Battuvshin Lkhagvasuren
  • Enkhnaran Tumurbaatar ▸
Submitted
December 24, 2025
Published
December 31, 2025

Abstract

Fatigue, a prevalent condition impacting biological, psychological, and cognitive functions, affects 30–50% of the general population, with heightened prevalence (52–70%) post-COVID-19. The Chalder Fatigue Scale (CFS) is a widely used tool to assess physical and mental fatigue, but its psychometric properties in healthy Mongolian adults are underexplored. This study aimed to culturally adapt and validate the Mongolian version of the CFS, evaluating its reliability and validity per COSMIN guidelines. A cross-sectional and longitudinal study was conducted with 941 healthy Mongolian adults (500 for validation, 441 for test-retest). The CFS was adapted following Beaton et al.’s (2000) guidelines: translation, synthesis, back-translation, expert review, and pilot testing (n = 21, CVI = 1.0). Participants completed the CFS, Hospital Anxiety and Depression Scale (HADS), Brain Overwork Scale (BOS), WHOQOL-BREF, and Pittsburgh Sleep Quality Index (PSQI). Reliability was assessed via Cronbach’s α and intraclass correlation coefficients (ICC) over a 14-day interval. Validity was evaluated through exploratory factor analysis (EFA), confirmatory factor analysis (CFA), and Pearson’s correlations for criterion and convergent validity. The Mongolian CFS demonstrated high internal consistency (Cronbach’s α = 0.877–0.920) and good test-retest reliability (ICC = 0.745). EFA confirmed a two-factor structure (physical and mental fatigue), explaining 57.25–64% of variance (KMO = 0.901–0.938, p < 0.001). CFA supported this structure (RMSEA = 0.08, CFI = 0.967, TLI = 0.951). Significant correlations with HADS (r = 0.330–0.500), BOS (r = 0.291–0.409), PSQI (r = 0.303–0.417), and negative correlations with WHOQOL-BREF (r = -0.313 to -0.505) confirmed criterion validity. Convergent validity was strong (r = 0.678–0.866). The Mongolian CFS is a reliable and valid tool for assessing fatigue in healthy adults, suitable for research and clinical applications in Mongolia.

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