The Prevalence of Voice Disorders and the Related Factors in University Professors: A Systematic Review and Meta-Analysis

Objective. This systematic review and meta-analysis aimed to estimate the prevalence of voice disorders and related factors in university professors. Methods. In this systematic review, Medline, Scopus, Embase, Cochrane Library, Eric, ProQuest, Magiran, Scientific Information Database and IranDoc databases were searched. The search was limited to January 1990 and May 2020. The inclusion criteria were reports of the prevalence of voice disorders in university professors and original studies in English and Persian languages. The exclusion criteria were studies assessing voice disorders in school or music teachers; the full-text not available; and case studies, conference papers, and review studies. All eligible studies were selected and critically appraised using the Joanna Briggs Institute checklist. Finally, a meta-analysis was performed using STATA 16.0 statistical software. Results. The preliminary search yielded 1251 articles and 18 of which met the eligibility criteria. The overall prevalence of voice disorders in university professors was 41% (Pooled prevalence: 0.41, 95% CI: 0.34-0.49, P-value < 0.001). Country-based analysis showed that the highest prevalence of voice disorders among university professors was in Iran 69% (Pooled prevalence: 0.69, 95% CI: 0.62-0.76) and the lowest was in China 20% (Pooled prevalence: 0.20, CI: 0.14-0.27). Among 4037 university professors, caffeine consumption was the most frequent related factor (87%) and dry throat was the most frequent symptom (46%). Conclusions.The present study yielded about 41% of the professors had voice disorders. Among the influential habits, caffeine consumption and among the symptoms, dry throat were very common in university professors. Due to the cross-sectional nature of our studies, we were not able to perform further analyses on the risk factors for voice disorders. Therefore, more longitudinal surveys are needed for reaching a more reliable and deep view into the development of voice disorders.