Investigating the Effect of a Vocal Hygiene Program on the Teaching Quality of Professors at Kermanshah University of Medical Sciences: A Quasi-Experimental Study

Abstract

Background: Teaching quality is critically important in higher education. Because oral communication is a primary modality for course delivery, university professors, as professional voice users, may be at risk of developing vocal problems over time. Adherence to a vocal hygiene program may be an effective strategy for protecting the voice and preventing voice problems during prolonged speech production in teaching sessions. Objectives: This study aimed to investigate the effect of a vocal hygiene program on teaching quality among university professors. Methods: This quasi-experimental study employed a pre-test–post-test control-group design. Forty professors from the basic sciences faculties at Kermanshah University of Medical Sciences (KUMS), Iran, in 2023 - 2024 were recruited by convenience sampling and allocated to the experimental or control group (n = 20 per group). Data were collected through interviews and a researcher-developed teaching quality questionnaire. The intervention consisted of a vocal hygiene program delivered in seven weekly sessions. Data were analyzed using paired-samples t-tests for within-group changes and analysis of covariance (ANCOVA) for between-group differences using SPSS version 26. Results: The sample included 23 men (57.5%) and 17 women (42.5%). After adjustment for covariates, including baseline values, professors' teaching quality improved significantly between the 2 groups at the end of the study (P = 0.001; F = 40.02; df = 1; effect size = 0.520). In addition, professors' teaching quality increased significantly from baseline after treatment in the experimental group (mean difference = 23.05; 95% CI, 18.09 to 28.01; P = 0.001). Conclusions: In this quasi-experimental study, professors who participated in a vocal hygiene program reported a statistically significant improvement in self-reported teaching quality. However, given the nonrandomized design, convenience sampling, and reliance on self-report measures, these findings should be interpreted as preliminary and context-specific. Further controlled studies with randomized allocation, objective assessments of teaching quality, and long-term follow-up are needed before this intervention can be broadly recommended.