Development and Validation of a Yoga-Based Intervention for Speech Dysfunction and Speech Difficulties Among Patients With Parkinson's Disease

Introduction Parkinson's disease (PD) is primarily thought to be brought on by the death of dopaminergic neurons in the substantia nigra pars compacta of the basal ganglia. Communication difficulties are a common symptom of PD, affecting both motor speech and language systems. These challenges significantly impact the quality of life by reducing participation in communication, leading to social withdrawal, and increasing the risk of social isolation and stigma among individuals with PD. There are no established yoga protocols specifically addressing speech problems in PD. Hence, the research team aimed to develop and validate the yoga program targeting speech dysfunction and speech difficulties among patients with PD. Materials and methods The first part of this study involved developing a yoga-based intervention based on a review of classic literature and recently published research papers in the area of yoga and voice culture on PD. In the second step, 30 subject matter experts (SMEs) (yoga) confirmed the proposed module. The content-validity ratio (CVR) was determined using Lawshe's formula. The content validity was scored by these 30 SMEs in an independent manner on a three-point scale (0-2), with 'not essential' receiving 0, 'useful but not essential' receiving 1, and 'essential' receiving 2. Results Of the 68 practices selected for validation, 33 practices had a CVR score of ≥0.333, indicating high content validity. Thirty-five practices had a CVR score of