Skip to main content
OpenTrials
Not Yet Recruiting

NCT Number: NCT07554378

A Multilevel Intervention to Prevent Noise Exposure in Farmworkers

This study will test a program to reduce noise exposure and prevent hearing loss among farmworkers. Farmworkers are often exposed to high levels of noise from machinery, which can lead to hearing loss over time.

Farms will be randomly assigned to either receive the program or serve as a comparison group. The program includes a short educational video, group discussion, and hands-on training on how to use hearing protection (such as earplugs). Supervisors will also receive brief training on how to support hearing protection use in the workplace.

Participants will wear a small device (dosimeter) during a work shift to measure noise exposure before the program and again about one month later. Participants will also complete surveys about their knowledge, attitudes, and behaviors related to hearing protection.

A subset of participants will be invited to take part in interviews to understand barriers and facilitators to using hearing protection and implementing the program.

The results of this study will help inform future efforts to improve hearing health and reduce noise exposure in agricultural settings.

Not Yet Recruiting

Trial opening soon.

Get Notified

Key information

Conditions

Noise Exposure Ear Diseases Hearing Disorders Hearing Loss Hearing Loss, Noise-Induced Hearing Loss, Sensorineural Nervous System Diseases Neurologic Manifestations Occupational Exposure Otorhinolaryngologic Diseases Pathological Conditions, Signs and Symptoms Sensation Disorders Signs and Symptoms

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

San Diego State University

San Diego, California, 92182, United States

Location contact

Laura Coco, PhD, AuD

CONTACT

[email protected]

619-594-3151

About this study

This study is a cluster randomized controlled trial designed to evaluate a multilevel intervention to reduce occupational noise exposure among farmworkers. Farms will be recruited through community and industry partnerships and randomized in a 1:1 ratio to either the intervention or control condition. Randomization will occur at the farm level to minimize contamination.

The intervention includes both worker- and supervisor-level components. Farmworkers will participate in a training session consisting of a brief educational video on noise exposure and hearing loss, followed by group discussion and hands-on instruction on proper use of hearing protection. Supervisors will receive a brief training focused on identifying noise hazards, promoting hearing protection use, and supporting workplace-level safety practices.

Control sites will not receive the intervention during the study period but will be offered the program after study completion.

Primary outcomes include objective measures of noise exposure assessed using personal dosimeters worn during a full work shift at baseline and approximately one month post-intervention. Dosimeters measure time-weighted average noise exposure, noise dose, and peak sound levels and do not record audio.

Secondary outcomes include farmworker knowledge, attitudes, self-efficacy, and behaviors related to hearing protection, as well as supervisor-level outcomes related to supporting hearing safety. Worksite-level outcomes include availability of hearing protection and presence of noise hazard indicators.

A qualitative component will be conducted with a subset of participants, including farmworkers, supervisors, and external stakeholders, to assess barriers and facilitators to implementation. Interviews will be conducted in participants' preferred language, audio-recorded with consent, and analyzed using established implementation science frameworks.

This study will provide preliminary evidence on the effectiveness and feasibility of a multilevel intervention to reduce noise exposure in agricultural settings and inform future large-scale trials.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Age 18 years or older
  • Currently employed as a farmworker or supervisor at a participating farm
  • Able to provide informed consent
  • Able to understand and communicate in Spanish or English

Exclusion criteria

  • Not currently working at a participating farm at the time of recruitment
  • Unable or unwilling to wear a personal noise dosimeter during a work shift
  • Unable to complete study procedures (e.g., surveys or training)

Treatment and study plan

Multilevel Hearing Protection Training

Behavioral

The intervention is a multilevel behavioral training program designed to reduce occupational noise exposure and promote hearing protection use. Farmworkers participate in a session that includes a brief educational video on noise exposure and hearing loss, group discussion, and hands-on instruction on proper use of hearing protection (e.g., earplugs). Supervisors receive a brief training on identifying noise hazards and supporting hearing protection use among workers. The intervention is intended to be delivered in a group or 1:1 setting by trained research staff or community health workers.

Other names: Protected Ears Project (PEP)

Primary outcomes

  1. Change in Time-Weighted Average Noise Exposure (dBA)

    Time frame: Baseline and approximately 1 month post-intervention

    Objective occupational noise exposure measured using personal dosimeters worn during a full work shift. The primary metric is time-weighted average (TWA) noise exposure in decibels (dBA), calculated using standard NIOSH criteria. Devices do not record audio, only noise levels.

  2. Change in Noise Dose (%)

    Time frame: Baseline and approximately 1 month post-intervention

    Cumulative occupational noise exposure measured as percent noise dose using personal dosimeters worn during a full work shift, calculated using standard NIOSH criteria.

Secondary outcomes

  1. Change in Hearing Protection Beliefs and Attitudes

    Time frame: Baseline and approximately 1 month post-intervention

    Change in self-reported beliefs and attitudes toward hearing protection use, assessed using the 14-item Hearing Protection Beliefs scale. Items are rated on a 4-point Likert scale (1 = disagree to 4 = strongly agree) and summed after reverse-coding negatively worded items. Total scores range from 14 to 56, with higher scores indicating more favorable and accurate beliefs about hearing protection.

  2. Acceptability of the Hearing Protection Training

    Time frame: Approximately 1 month post-intervention

    Participant-reported acceptability of the training assessed immediately post-training using the Acceptability of Intervention Measure (AIM). The AIM consists of 4 items rated on a 5-point Likert scale (1 = completely disagree to 5 = completely agree). Item responses are averaged to generate a mean score ranging from 1 to 5, with higher scores indicating greater perceived acceptability of the training.

  3. Appropriateness of the Hearing Protection Training

    Time frame: Approximately 1 month post-intervention

    Participant-reported appropriateness of the training assessed immediately post-training using the Intervention Appropriateness Measure (IAM). The IAM consists of 4 items rated on a 5-point Likert scale (1 = completely disagree to 5 = completely agree). Item responses are averaged to generate a mean score ranging from 1 to 5, with higher scores indicating greater perceived appropriateness of the training.

  4. Feasibility of the Hearing Protection Training

    Time frame: Approximately 1 month post-intervention

    Participant-reported feasibility of the training assessed immediately post-training using the Feasibility of Intervention Measure (FIM). The FIM consists of 4 items rated on a 5-point Likert scale (1 = completely disagree to 5 = completely agree). Item responses are averaged to generate a mean score ranging from 1 to 5, with higher scores indicating greater perceived feasibility of the training.

Study contacts

Contact information is provided by the study sponsor or research team.

Laura Coco, PhD, AuD

CONTACT

[email protected]

16195943151

Sponsors and collaborators

Lead sponsor

San Diego State University

Other

Collaborators

  • National Institute on Deafness and Other Communication Disorders (NIDCD)

Registry information

Acronym: POP

Important dates

Study start
2026
Primary completion
2031
Study completion
2032
First posted
Apr 28, 2026
Registry last updated
Apr 28, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.