Normative data on teachers’ voice use in real-life situations

Abstract

Background As part of their working routine, teachers use their voice for extended periods of time. To compensate for adverse acoustic conditions and background noise, they are also required to speak at high intensities. Since teaching is acknowledged to be vocally demanding, several studies have investigated teachers’ vocal load, that is, the stress inflicted on the larynx during vocalization, which is thought to be influenced by duration, intensity and frequency of phonation. A promising method for analyzing teachers’ phonatory behavior in real-life situations is the use of a portable voice dosimeter that objectively documents vocal parameters. Depending on several factors, those parameters may vary within the teaching profession (Masuda et al., 1993; Morrow and Connor, 2011; Remacle, Morsomme, and Finck, 2014). With the aim of quantifying their vocal parameters and identifying the most at-risk teaching conditions, we have established a large database of French-speaking teachers. Based on this database, this study analyzed vocal loading differences with regard to gender, teaching level, and environment (professional versus extra-professional). Methods Seventy-six French-speaking teachers (15 males and 61 females) were monitored during one workweek using the Ambulatory Phonation Monitor voice dosimeter (KayPENTAX). The subjects included 21 kindergarten, 20 primary and 35 secondary school teachers. All male subjects were in the latter group. The vocal parameters analyzed were phonation time, intensity and fundamental frequency (F0). Results The statistical analysis revealed that, irrespective of gender, phonation time, F0 and intensity level were significantly higher in the professional environment than the extra-professional environment (p<.01). Among female subjects, the F0 of kindergarten teachers was significantly higher than that of primary school teachers, which in turn was higher than that of secondary school teachers (p<.01). The phonation time and intensity were also higher in female kindergarten teachers than other female teachers, but this difference did not reach significance. As expected, regarding gender differences, we found that female secondary school teachers spoke with significantly higher F0 than their male colleagues (p<.001). In the extra-professional setting, they also spoke with a significantly higher intensity (p<.05), but no such effect was found in the professional environment. Conclusion Overall, our subjects showed an increase in vocal loading parameters when they were at work compared to their free time. This confirms the results of earlier studies and demonstrates that teaching is an occupation with remarkably high vocal demands. The analysis of mean frequency showed that lower school levels were associated with higher-pitched voice. It can be assumed that kindergarten teachers adapt to the higher F0 of their young pupils and that their effort to maintain the pupils’ attention results in greater frequency variations. References Masuda, T., Ikeda, Y., Manako, H., & Komiyama, S. (1993). Analysis of vocal abuse: Fluctuations in phonation time and intensity in 4 groups of speakers. Acta Oto-Laryngologica, 113(3), 547–552. Morrow, S. L., & Connor, N. P. (2011). Comparison of voice-use profiles between elementary classroom and music teachers. Journal of Voice, 25(3), 367–372. Remacle, A., Morsomme, D., & Finck, C. (2014). Comparison of vocal loading parameters in kindergarten and elementary school teachers. Journal of Speech, Language, and Hearing Research, 57(2), 406–415