Effectiveness of Virtually Simulated Intervention for Patients Having Stuttering

This study is a randomized controlled trial designed to evaluate the effectiveness of a culturally adapted virtual reality (VR)-based speech restructuring intervention for individuals with stuttering in Pakistan. The intervention has been developed to simulate everyday communication situations within a controlled, immersive, and progressively challenging virtual environment. The overall objective of the trial is to determine whether VR-based speech restructuring can improve speech fluency and reduce stuttering severity and associated behavioral, physiological, and communication-related difficulties.

The VR intervention consists of five culturally appropriate communication scenarios representing commonly encountered real-life speaking situations in the Pakistani context: lecture hall, grocery store, restaurant, telephone conversation, and job interview. The scenarios incorporate graded levels of communication difficulty and are designed to provide opportunities for participants to practice speech restructuring techniques in progressively challenging situations. The intervention includes realistic environmental sounds, interactive avatars of different ages and genders, adjustable audience size and positioning, emotional expressions, varying question types, distractors, time-limited speaking tasks, relaxation exercises, and opportunities for repeated practice of speech restructuring techniques.

The intervention will be delivered using the Oculus Quest 2 head-mounted display. A neutral adaptation environment will be used to familiarize participants with the VR equipment and virtual environment before exposure to the therapeutic scenarios. Standard operating procedures (SOPs) will be followed to ensure standardized equipment setup, participant orientation, intervention delivery, and safety throughout the study. The intervention protocol and VR scenarios were developed and refined through a structured development process, including literature review, observation of real-life communication situations, brainstorming and ideation, storyboard development, live-action role plays, conversion into immersive virtual environments, and expert review. Content validity of the developed scenarios was established through evaluation by six experts with relevant professional experience using the Content Validity Index (CVI).

Eligible participants with stuttering will be recruited according to predefined inclusion and exclusion criteria. Participants will be randomly allocated to the experimental group or control group. The experimental group will receive the VR-based speech restructuring intervention consisting of 16 therapy sessions conducted three times per week, with each session lasting approximately 25 minutes. The intervention will begin with orientation to the VR system and training in the speech restructuring techniques. Participants will then practice the techniques within the five virtual communication scenarios, with the level of difficulty progressively increased according to the intervention protocol. Later sessions will focus on integrating skills across different communication situations and facilitating the transfer of learned speech restructuring strategies to real-life communication environments.

Participants in the control group will receive the control condition specified in the study protocol. Both groups will undergo outcome assessment at predefined time points. Baseline assessment will be conducted before commencement of the intervention, followed by an interim assessment during the intervention and a post-intervention assessment after completion of the 16 sessions. The primary outcome will be the severity of stuttering. Secondary outcomes will assess speech fluency, communication attitudes and emotions, associated motor behaviors, physiological factors associated with stuttering, and participants' sense of presence within the virtual environment, where applicable.

Speech fluency and stuttering-related outcomes will be assessed using standardized and structured assessment procedures. Outcome measures will include real-time analysis of speech fluency and dysfluency index, assessment of physiological factors associated with stuttering, the Modified S Scale for communication attitudes and emotions, assessment of associated motor behaviors, and the Presence Questionnaire for evaluating participants' experience within the virtual environment.

Data will be analyzed using SPSS. Descriptive statistics will be used to summarize participant characteristics and outcome measures. Appropriate inferential statistical tests will be used to compare changes in outcome measures between the experimental and control groups and across the predefined assessment time points. Statistical significance will be determined according to the prespecified analysis plan. The results of this randomized controlled trial will provide evidence regarding the effectiveness of a culturally adapted VR-based speech restructuring intervention for individuals with stuttering and its potential application as an adjunct or alternative approach to conventional stuttering intervention.