Objective voice analysis in elementary school teachers

Document Type : Original Article


Speech Therapy Dept., Rehabilitation Sciences, Zahedan University of Medical Sciences, Zahedan,Iran.


Introduction. The aim of the present study was to examine a number of vocal acoustic parameters in a group of male and female elementary school teachers in comparison to their normal peers.

Materials and Methods. Fifteen female and 15 male primary schoolteachers in the age range of 35–40 years with 15 years teaching experience volunteered to participate in the study. The control group consisted of similar age who they were not teacher (15 men and 15 women). Recordings and audio signal analyses were carried out using Praat software. Each subject was asked to sustain the vowel /^a/ using habitual and constant vocal pitch, loudness, and quality for at least 5 seconds. Five tokens from each subject were obtained.

Results. For the male subjects, the results indicated no significant difference (at the 0.05 level) for each variable between the two groups. However, for the female subjects, t tests showed significant differences between the teachers and the nonteacher controls in all parameters at the 0.01 level. The female teachers had significantly lower F0 (190.27 Hz) than the control group (236.32 Hz). Also, for the perturbation acoustic parameters (jitter% and shimmer%) and harmonics-to-noise ratio the female teacher group had significantly higher values than their corresponding control group.

Discussion.The results indicate that female teachers appear to be more susceptible to voice stability change than the male teachers. Also, acoustic analysis of voice for teachers may significantly contribute to the objective voice examination of this group.


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