Vocal effectiveness of speech-language pathology students: Before and after voice use during service delivery

Background: As a professional voice user, it is imperative that a speech-language pathologist's (SLP) vocal effectiveness remain consistent throughout the day. Many factors may contribute to reduced vocal effectiveness, including prolonged voice use, vocally abusive behaviours, poor vocal hygiene and environmental factors. Objectives: To determine the effect of service delivery on the perceptual and acoustic features of voice. Method: A quasi-experimental., pre-test-post-test research design was used. Participants included third-and final-year speech-language pathology students at the University of Pretoria (South Africa). Voice parameters were evaluated in a pre-test measurement, after which the participants provided two consecutive hours of therapy. A post-test measurement was then completed. Data analysis consisted of an instrumental analysis in which the multidimensional voice programme (MDVP) and the voice range profile (VRP) were used to measure vocal parameters and then calculate the dysphonia severity index (DSI). The GRBASI scale was used to conduct a perceptual analysis of voice quality. Data were processed using descriptive statistics to determine change in each measured parameter after service delivery. Results: A change of clinical significance was observed in the acoustic and perceptual parameters of voice. Conclusion: Guidelines for SLPs in order to maintain optimal vocal effectiveness were suggested.