Evaluation of loudness intolerance amoung general factory workers

Title: Evaluation of Loudness Intolerance Among General Factory Workers

Type of Study: Prospective cross-sectional study

Aims & Objectives:

1. Quantify noise exposure among factory workers exposed to occupational noise.

2. Assess loudness intolerance in individuals with occupational noise exposure.

3. Correlate noise exposure with loudness discomfort levels.

4. Justify study: This study is significant as loudness intolerance due to noise exposure is under-researched, despite its potential impact on workers’ auditory health.

Departments Involved: Department of Speech and Hearing

Study Period:

• IRC and IEC Approvals: 3 months

• Data Collection: June 2024 - February 2025

• Analysis & Thesis Submission: March 2025

Sample Size:

• Estimated Sample Size: 41

• Calculation: Based on correlation coefficient (r = 0.425), 80% power, and 5% significance level.

Materials and Methods:

- Inclusion Criteria:

• Adults (20-50 years)

• Exposed to occupational noise for over a year

• Normal to mild hearing loss (Pure Tone Average: 15-40 dB HL)

- Exclusion Criteria:

• Significant medical illnesses (e.g., hypertension, diabetes)

• Conductive hearing loss

Biological Materials Required: None

Statistical Methods:

• Software: Jamovi version 2.3.28

• Tests: Shapiro-Wilk test for normality, descriptive statistics, Pearson/Spearman correlation.

Tools Used:

• Noise Exposure Questionnaire (NEQ): Assesses annual noise exposure; reliable, permission obtained.

• Modified Khalfa Hyperacusis Questionnaire (HQ): Assesses loudness intolerance; validated, permission obtained.

Procedure:

1. Obtain ethical and CTRI approvals.

2. Measure factory noise levels with a Sound Level Meter (SLM).

3. Screen workers with a portable audiometer.

4. Administer NEQ and HQ questionnaires.

5. NEQ determines annual noise exposure (LAeq8760h). HQ assesses loudness intolerance, with scores indicating severity.

Outcome Measures:

• Hearing Sensitivity: Measured in dB HL.

• Questionnaire Scores: NEQ for noise exposure, HQ for loudness intolerance.

Potential Risks and Benefits:

• Risks: Possible mental exhaustion and disruption of work.

• Benefits: Contributes to understanding the impact of noise exposure and loudness intolerance, potentially guiding future auditory health measures.

Ethical Considerations:

• Obtain IEC and IRC clearances and CTRI approval.

• Informed consent from participants.

• Confidentiality of data.

• Participants will receive some form of reinforcement.

Budget:

• Not applicable

Review of Literature:

• Workers in noisy environments are at increased risk of loudness intolerance, alongside other auditory issues such as tinnitus and hearing loss. Prior research mainly focuses on hearing loss, with limited studies on loudness intolerance. This study aims to fill the gap by exploring how noise exposure affects loudness intolerance, essential for effective auditory rehabilitation and worker protection in noisy environments.