Comparison of Jitter, Shimmer and S/Z Ratio in Multiple Sclerosis Patients

Document Type : Original Article


1 Speech Therapy Department, School of Rehabilitation, Jundishapour University of Medical Sciences, Ahvaz, Iran

2 Assistant Professor of Physiotherapy. Department of Speech Therapy, Musculoskeletal Rehabilitation Research Center, Ahvaz Jundishapur University of Medical Science,Ahvaz, Iran.

3 Assistant Professor of Physiotherapy.Department of Speech Therapy, Musculoskeletal Rehabilitation Research Center, Ahvaz Jundishapur University of Medical Science,Ahvaz, Iran.


Background and Objective: The aim of this article is to compare, jitter, and shimmer and s/z ratio in multiple sclerosis (MS) patients with normal individuals in same age.
Subjects and Methods: The methodology of this study was controlled cross-sectional that was carried out with 60 individuals (30 MS, 30 Normal). Both groups were 15 males and 15 females from 21 to 51 years. Exclusion criteria were prior laryngeal disorder, any larynx surgery, tracheotomy, tumors, larynx, and lung cancer, respiratory disease, and other associated diseases. Associations were assessed by using T-test.
Results: There was no association between MS and jitter (p=0/25), and shimmer (p=0/34) as well. However, association was found between MS and s/z ratio (p=0.00). The s/z ratio was higher in normal individuals than in MS patients.
Conclusion: Results indicate that MS can affect s/z ratio as well as assessment and treatment of MS patient. Therefore, speech patholologist should be aware of voice Acoustic parameters variations in these patients.


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