Effect of Clinical Expertise on Efficacy of Vocal Function Exercises in Individuals With Typical Voice

Objectives/Hypothesis: To determine the effect of clinical expertise on efficacy of Vocal Function Exercises (VFEs) as measured by change in percent of maximum phonation time goal attained. The hypothesis was that clinical expertise would result in greater increases in percent of maximum phonation time goal attained. Study Design: Randomized controlled trial. Methods: A convenience sample of 19 individuals with typical voice was recruited in a university academic clinic setting. All participants completed baseline assessment and 17 completed all study procedures. Participants were randomized to receive VFEs from an expert voice clinician with more than 40 years’ experience (expert group (EG)) or from a master's student in Communication Sciences and Disorders trained in VFEs (novice group (NG)). The primary outcome measure was change in percent of maximum phonation time goal attained during VFE tasks 1 and 4. Results: Mean change scores for maximum phonation time were 27.71 (P = 0.001) and 25.31 (P = 0.003) for EG and NG, respectively. Both groups improved significantly on the primary outcome measure, but the difference between groups was not statistically significant (P = 0.759). A Hedges’-g effect size of −0.14 [−1.10, 0.81] was obtained comparing EG and NG groups, indicating a small negative effect of limited clinical expertise on VFE outcomes in individuals with typical voice. Conclusions: Speech-language pathologists with varied levels of expertise are capable of efficaciously administering VFEs in individuals with typical voice.