Systematic Review of Literature on Prevalence of Vocal Fatigue Among Teachers

Previous results suggest that teaching is a high-risk profession for developing voice disorders. This study aims to determine the prevalence of vocal fatigue among teachers and its relationship with voice acoustic parameters reported in previous studies. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement Guidelines, we performed a systematic literature review including five databases: Scopus, Scielo, ScienceDirect, PubMed, and Web of Science. Information on study population, definition and evaluation of vocal fatigue, and teaching characteristics were extracted from each paper. The quality of the included publications was assessed using the "Quality assessment tool for quantitative studies". In total, 14 publications met the inclusion criteria. The two most common work-related factors of vocal fatigue were high levels of noise inside classrooms and loud speaking voice use. Some investigations reported voice acoustic parameters such as fundamental frequency and vocal Sound Pressure Levels as associated with vocal fatigue. Vocal fatigue is a prevalent symptom among teachers associated with teaching vocal demands. However, studies on objective parameters that complement self-reports, to quantify vocal fatigue are needed to determine permissible values for healthy occupational voice use.