Subjective self-ratings through a prolonged reading task in dysphonic versus normophonic female teachers

Aim: The purpose of this study was to evaluate the impact that a 2-hour reading task could have on ones voice in 16 normophonic and 16 dysphonic female teachers. Method and material: Teachers’ voices were orally loaded by reading a novel. They were instructed to read for imaginary students, as in their classroom. Voice intensity was constantly controlled between 70 and 75 dB. Every 30 minutes, participants were asked to answer the following questions using a 100-mm horizontal visual analogue scale: 1) How is your voice quality? 2) Do you feel any phonation effort? 3) Do you feel any vocal fatigue? and 4) Do you feel any laryngeal discomfort? Results and conclusions: For all subjective self-ratings, the repeated measures ANOVA demonstrated significant main effects of the duration (p < 0.0001) and of the group (p < 0.05). Subjects of both groups reported a worsening of their voice quality during the reading while phonation effort, vocal fatigue and laryngeal discomfort increased. Surprisingly, no significant interaction between duration and group was found. This means that subjective self-ratings realized before and during the reading task depict a similar evolution of both groups, while we expected more worsening of voice through time in the dysphonic group

Vocal Impact of a Prolonged Reading Task in Dysphonic versus Normophonic Female Teachers

OBJECTIVES: This study evaluates the impact on voice of a 2-hour reading task between 70-75 dB(A) in 16 normophonic and 16 dysphonic female teachers with vocal nodules. METHODS: Objective measurements (acoustic analysis, voice range measurements, aerodynamic measurements) and subjective self-ratings were collected before the task and every 30 minutes during the reading to determine the voice evolution in both groups. RESULTS: Fundamental frequency, lowest frequency, highest frequency (F-High), highest intensity and intensity range increase through the reading, whereas Shimmer decreases. Maximum phonation time decreases after 30 minutes. Estimated subglottal pressure (ESP) and sound pressure level increase during the first hour. Afterwards, ESP decreases. Self-ratings worsen through time. When comparing the normophonic and the dysphonic teachers, self-ratings reveal more complaints in the dysphonic group. Few differences in objective measurements are found between both groups: normophonic teachers show lower ESP, higher F-High and greater frequency range. CONCLUSIONS: Frequency modifications from acoustic analysis and voice range measurements suggest an increased laryngeal tension during vocal load, while subjects perceive a worsening of voice. Aerodynamic parameters depict first a deterioration of voice efficiency and then an adaptation to the prolonged reading. The comparison between both groups shows a discrepancy between objective measurements and self-ratings, suggesting that both approaches are necessary to have a complete view of vocal load effects. Surprisingly, both groups behave similarly through vocal load, without more or quicker deterioration of voice in the dysphonic group