Efficacy of the Water Resistance Therapy Program Delivered via Telepractice and In-Person: A Noninferiority, Randomized, and Blinded Clinical Trial

PURPOSE: This noninferiority randomized clinical trial aimed to analyze the effectiveness of water resistance therapy (WRT) delivered via telepractice compared to in-person therapy. Therapy adherence was also investigated. METHOD: Adults aged 18-50 years diagnosed with behavioral dysphonia, with little to no prior experience with vocal exercises and access to the internet, were included in the study. A total of 23 participants were randomly allocated through stratified randomization into either the in-person therapy group (IPG) or the telepractice therapy group (TPG). All participants underwent an eight-session WRT program using a silicone tube submerged in water, with each session lasting 30 min. Voice therapy in the TPG followed American Speech-Language-Hearing Association guidelines, with participants instructed to be in a quiet, private room and to use earphones during the sessions. Outcomes were assessed at three time points: baseline, posttreatment, and 1-month follow-up. The analysis included electroglottographic measures (vocal economy-quasi-output cost ratio), acoustic analysis, auditory-perceptual assessment, and self-assessment. RESULTS: Vocal economy, acoustic, and perceptual measures demonstrated the noninferiority of telepractice compared with in-person therapy. However, in the self-assessment domain, improvements were observed only in the IPG. Treatment effects remained stable at follow-up in both groups. CONCLUSIONS: Vocal economy, acoustic, and perceptual measures support the noninferiority of delivering WRT via telepractice compared to in-person therapy. However, the lower improvement in self-perception among participants in the telepractice group suggests that in-person interactions may offer additional benefits in terms of subjective experience. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.32160219.