A Comparison of Dysphonia Severity Index in Female Teachers With and Without Voice Complaints in Elementary Schools of Tehran, Iran

Abstract

Background Teachers are the greatest group of professional voice users. Prolonged, continuous speaking in a loud voice at school may entail a bad vocal health. It seems that their occupational circumstances make them more likely to develop voice disorders in comparison with other groups. Objectives The purposes of this study are 1) to compare teachers with and without voice complaint on the Dysphonia Severity Index and 2) to compare component measures that establish Dysphonia Severity Index. Materials and Methods This study included 40 female teachers with voice complaint and 40 female teachers without voice complaint between the ages of 30 and 50 years who were teaching in elementary schools of Tehran city. Simple non-random sampling was done for selected teachers in two groups. The examinees were asked to produce the vowel /a/ three times for calculating any variables, then measures of maximum phonation time, jitter, highest phonational frequency, and lowest intensity were obtained for each subject with Praat and Phonetogram softwares and incorporated into multivariate Dysphonia Severity Index formula. Kolmogoro- Smirnov one sample test and independent sample T-Test was used, the significance level was set at P < 0.05. Results Results indicate that female teachers without voice complaint have significantly higher Dysphonia Severity Index scores than female teachers with voice complaint (mean Dysphonia Severity Index: 3.58 vs. 1.05, respectively), also significant differences are observed between groups of with and without complaint for four of components of the DSI (F0 high, I low, jitter and maximum phonation time) (P value = 0.001). Conclusions The findings of this study indicate that there is a significant difference in Vocal Quality between teachers with and without voice complaint. This finding may indicate teachers with voice complaint have worse vocal quality that means they are at risk for voice problems. This information may be very important for voice professionals and, speech and language pathology to advice teachers with voice complaint and manage to advocate "good vocal health".