Measuring Vocal Fatigability in Teachers: The Vocal Fatigability Scale for Teachers (VFS-T)

OBJECTIVES: This study focuses on the distinction between vocal fatigability and vocal fatigue, highlighting the importance of vocal fatigability in assessing teachers’ quality of life. Vocal fatigability is more critical for quality of life evaluation than performance or perceived vocal fatigue because it considers the accumulation and chronicity of fatigue over isolated tasks. The objectives are to develop and validate the Vocal Fatigability Scale for Teachers (VFS-T), to assess teachers’ levels of vocal fatigability, and to analyze variations based on personal and occupational traits. The VFS-T construct encompasses items related to vocal sensations and performance, their connection to accumulated demanding vocal activity, descriptions of recovery strategies, necessary rest periods, and the impact of vocal fatigue on daily activities.
STUDY DESIGN: A cross-sectional study employing a single group and an ex post-facto design was conducted.
METHODS: The sample consisted of 184 active teachers with various vocal conditions who participated in the study. They completed the VFS-T questionnaire, provided personal and occupational data, and completed the VHI-10 questionnaire. The data collected were analyzed for item refinement, internal structure, reliability, validity, diagnostic capacity, cutoff values, and group differences.
RESULTS: The item refinement and internal structure analysis reveal a scale comprising 17 items grouped into two factors. The VFS-T shows good reliability and validity, with cutoffs at 28 for high fatigability. Most teachers fall into the moderate fatigability range, with 72% experiencing vocal fatigability.
CONCLUSIONS: The VFS-T is a reliable tool for detecting vocal fatigability in teachers. This scale focuses on the construct of vocal fatigability, which is related to chronicity of vocal fatigue and limitations in daily activities in teachers.