Otoacoustics Emissions Contralateral Supression Test
Phase: NA
Conditions: Multiple Sclerosis, Obesity, Hearing Loss
Sponsor: Ondokuz Mayıs University

Clinical Study Document
Study Title:
The Effect of Obesity on Contralateral Suppression in Patients with Multiple Sclerosis
NCT Number:
NCTXXX
Document Date:
August 14, 2025

Statistical Analysis Plan
Statistical Analysis Plan
Data were analyzed using SPSS version 21 (Statistical Package for the Social Sciences). The normality of the
data was assessed using the Shapiro-Wilk test. Data were tested for conformity to a normal distribution. For
normally distributed data, mean  standard deviation (x  SD) was used, while for non-normally distributed data,
median (minmax) was reported. Students t-test was applied for comparisons between groups when data
followed a normal distribution, whereas the Mann-Whitney U test was used for non-normally distributed data.
Chi-square analysis was performed to evaluate relationships between categorical variables. Results were
interpreted with a 95% confidence interval, and statistical significance was set at P < 0.05.
Sample Size Calculation
The sample size was calculated using G*Power (version 3.1.7). Based on a previous study that reported a large
effect size (Cohens d = 0.8), an a priori power analysis was conducted. The analysis revealed that a total of 52
participants (26 per group) would be required to achieve a power of 0.80 with a significance level of 0.05
(two-tailed).

Study Protocol
Study Title
The Relationship Between Anthropometric Measurements and Efferent Auditory System in Patients with
Multiple Sclerosis
Study Objectives
This study aims to investigate the relationship between anthropometric measurements (such as BMI) and the
function of the efferent auditory system, measured by contralateral suppression of distortion product
otoacoustic emissions (DPOAEs), in individuals diagnosed with Multiple Sclerosis (MS).
Study Design
This is a cross-sectional observational study. Participants will be assessed at a single time point within 12
months following their diagnosis of MS. Data collection will include demographic information,
anthropometric measurements, and DPOAE testing with contralateral suppression.
Participants and Eligibility Criteria
Inclusion Criteria:
- Age between 18 and 50 years
- Confirmed diagnosis of Multiple Sclerosis
- Ability to cooperate with the procedures
- Normal ENT and otoscopic examination
- No history of noise exposure
- Not pregnant or menstruating (for female participants)
Exclusion Criteria:
- Presence of middle ear pathology
- Abnormal tympanometry
- Hearing loss > 20 dB HL between 500-4000 Hz
- Other neurological or psychiatric disorders
- Use of ototoxic medication
- History of otologic surgery or trauma

- BMI < 18.5 or > 40
- Diagnosis of metabolic or endocrine disorders
Study Procedures
Participants will complete a demographic questionnaire and undergo anthropometric measurement. DPOAE
testing will be conducted in a sound-treated room using standardized protocols. Contralateral suppression will
be measured by presenting noise to the opposite ear during DPOAE recording.
Ethical Considerations
The study has been approved by the Ondokuz Mays University Clinical Research Ethics Committee. All
participants will provide written informed consent before participation. The study involves no risk to the
participants and their personal data will be kept confidential.

Ethics Committee Approval (English Translation)
Institution
Ondokuz Mays University Clinical Research Ethics Committee
Details
Committee Registration Number: [Insert if available]
Address: Kurupelit Campus, 55139 Atakum / Samsun, Turkey
Phone: +90 362 312 19 19 (Ext: 2782)
Email: samsunkaek@omu.edu.tr
Approval Details
Date of Approval: June 11, 2025
Protocol Number: 2022/300
Applicant: Dr. Asuman Kkner
Project Title: The Effect of Obesity on Contralateral Suppression in Patients with Multiple Sclerosis
Statement
The Clinical Research Ethics Committee of Ondokuz Mays University has reviewed and approved the
above-mentioned research project in its session dated June 11, 2025, in accordance with the relevant ethical
principles and national regulations on clinical research involving human participants.
This approval includes the review of the study protocol, informed consent forms, and participant information
sheets. The researcher is responsible for conducting the study in compliance with ethical standards.
Signature
Signed on behalf of the Ethics Committee
Prof. Dr. Ramis olak
Chair, Ondokuz Mays University Clinical Research Ethics Committee