Evaluating a Digital Speech Therapy App for Stuttering: A Pilot Validation Study

TL;DR

Stuttering affects fluency and quality of life, with traditional therapy often limited by access and cost. This study pilots Eloquent, a self-guided digital therapy app, evaluating its impact on fluency and communication attitudes using SSI-4 and S24 in a 15-session protocol with blinded assessments. Results show a 52.7% reduction in SSI-4 total scores, with large gains in physical symptoms, duration, and reading/spoken tasks, and a 33.5% reduction in S24 scores, indicating improved confidence. The findings support digital, scalable interventions as feasible options for adults who stutter and highlight the need for larger, controlled trials to establish durability and generalizability, as well as exploration of hybrid therapist-guided models.

Abstract

Stuttering is a clinical speech disorder that disrupts fluency and leads to significant psychological and social challenges. This study evaluates the effectiveness of Eloquent, a digital speech therapy app for stuttering, by analyzing pre-therapy and post-therapy speech samples using the Stuttering Severity Index-4 (SSI-4) and the S24 communication and attitude scale. Results showed a 52.7% reduction in overall SSI-4 scores, with marked improvements in reading (45%), speaking (46%), duration (57%), and physical concomitants (63%) scores. Over 75% of participants improved by at least one severity category. S24 scores decreased by 33.5%, indicating more positive self-perceptions of speech and reduced avoidance. These findings highlight the potential of structured, technology-driven speech therapy interventions to deliver measurable improvements in stuttering severity and communication confidence.

Figures (1)

• Figure 1: Screenshots from Eloquent: The home screen showing progress and metrics (left); Metronome tool to practice rhythmic speech cueing (center); Virtual avatar that simulates the experience of speaking to a real person (right)