Children with speech sound disorder show diminished intelligibility in spoken communication and may thus be perceived as less capable than peers, with negative consequences for both socioemotional and socioeconomic outcomes. New technologies have the potential to transform interventions for speech sound disorder, but there is a lack of rigorous evidence to substantiate this promise. This research will meet a public health need by systematically evaluating the efficacy of visual-acoustic biofeedback intervention delivered in-person versus via telepractice.

The objective of this study is to test the hypothesis that treatment incorporating visual-acoustic biofeedback can be delivered via telepractice without a significant loss of efficacy. Participants will be randomly assigned to receive identical treatment either via online telepractice or in the laboratory setting. The same software for visual-acoustic biofeedback, staRt, will be used in both conditions. Participants' progress in treatment will be evaluated based on blinded listeners' perceptual ratings of probes produced before and after treatment. Pre and post treatment evaluations will be carried out in person for all participants.

This study aims to test the working hypothesis that biofeedback treatment delivery via telepractice will not be associated with a reduction in efficacy that exceeds a maximum acceptable value determined a priori. In a prospective randomized controlled non-inferiority trial, children will be randomly assigned to receive a standard course of visual-acoustic biofeedback intervention delivered in-person or via telepractice. Progress will be measured with blinded listeners' ratings of untreated words produced before and after treatment. A survey will also be administered before and after treatment to assess changes in participants' participation and socio-emotional well-being, as well as participants' and caregivers' satisfaction with the therapy experience.

Inclusion Criteria:

• Must be between 9;0 and 17;11 (years;months) old at the time of enrollment.
• Must speak English as the dominant or equally dominant language
• Must have begun learning English by age 3, per parent report.
• Must hear a rhotic dialect of English from at least one speaker in the home if the home language is English.
• Must pass a pure-tone hearing screening.
• Must pass a brief examination of oral structure and function.
• Must exhibit less than thirty percent accuracy, based on trained listener ratings, on a probe list eliciting /r/ in various phonetic contexts at the word level.
• Must demonstrate age-appropriate receptive and expressive language abilities on the Clinical Evaluation of Language Fundamentals-5 (CELF-5).
• Must have access to a laptop or desktop computer for study sessions in the event of randomization to the telepractice condition.
• Must have home wifi sufficient to support video calls in the event of randomization to the telepractice condition.

Exclusion Criteria:

• Must not exhibit voice or fluency disorder of a severity judged likely to interfere with the ability to participate in study activities.
• Must not currently have orthodontia that crosses the palate and cannot be removed.
• Must not have history of permanent hearing loss.
• Must not have an existing diagnosis of developmental disability such as cerebral palsy or Down Syndrome.
• Must not have history of major brain injury, surgery, or stroke in the past year.
• Must not have epilepsy with active seizure incidents with in the past 6 months.
• Must not show clinically significant signs of apraxia of speech or dysarthria.

A manual of procedures and materials for treatment and clinician training will be released through the Open Science Framework (OSF). Complete de-identified data and analysis scripts on OSF will also be released when the study is completed.

OSF as projects are completed

Data will be shared within 6 months of the study end date (7/31/28) and will be made available indefinitely.

Publicly accessible

All perceptual ratings will be obtained from blinded, naive listeners recruited through online crowdsourcing. Following protocols refined in previous published research, binary rating responses will be aggregated over at least 9 unique listeners per token.