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Active, Not Recruiting

NCT Number: NCT04172766

Apple Hearing Study

The Apple Hearing Study is a partnership between the University of Michigan and Apple to study sound exposure and its impact on hearing health. This groundbreaking study will advance the understanding of how hearing could be impacted over time by exposure to sound at certain levels. The investigators will measure headphone and environmental sound exposures over time among participants, and determine how these exposures impact hearing and stress levels. US residents who own an iPhone, download the Apple Research app and consent to participate will be randomly assigned to two groups, one with a "Basic" user interface in the Research app, and one with an "Advanced" user interface. Users in the "Advanced" group will receive additional information about their exposures and be given additional surveys and hearing tests based on their music and environmental sound exposures. The study will provide investigators with a better understanding of listening behavior and its overall impact on hearing health. This information will in turn help guide public health policy and prevention programs designed to protect and promote hearing health in the US and globally.

Active, Not Recruiting

This study is active but is not currently recruiting participants.

Key information

Conditions

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

Age range

18 year and older

Sex eligibility

All sexes

Study type

Observational

Primary location

University of Michigan School of Public Health

Ann Arbor, Michigan, 48109, United States

Who can participate

Healthy volunteers accepted: Yes

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

Inclusion criteria

  • Age ≥ 18 years at time of eligibility screening, ascertained from self-reported date of birth. Potential subjects in the states of Alabama and Nebraska must be 19 or older (legal age of consent in these states), and 21 and older for any subjects in Puerto Rico.
  • Live in the United States of America at time of eligibility screening, ascertained from self-report.
  • Proficient in written and spoken English, defined by self-report.
  • Participants must NOT share their iCloud account, iPhone or other devices such as Apple Watch with anyone else as this would make it challenging for researchers to use their information.
  • Possession of the following, ascertained from automatic hardware/software/device pairing check:
  • iPhone with iOS versions capable of supporting the Research app used to complete screening eligibility.
  • Optional: Apple Watch (any model) paired with iPhone; an Apple Watch Series 4 or later is required to share environmental sound levels.

Treatment and study plan

Primary outcomes

  1. Headphone audio level patterns

    Time frame: From enrollment to the end of followup at 10 years

    For the entire cohort over various timeframes

  2. Difference in Headphone Audio Level patterns

    Time frame: From enrollment to the end of followup at 10 years

    This will include assessment of sound pressure level and time at baseline and over the duration of the study.

  3. Association between Headphone Audio Level patterns and Pure Tone Audiometry

    Time frame: From enrollment to the end of followup at 10 years

    Analysis will occur for each tested frequency (dB HL at 125 Hz, 250 Hz, 500 Hz, 1 kHz, 2 kHz, 4kHz, and 8 kHz assessed for both ears) for both ears at baseline and over the duration of the study.

  4. Association between Headphone Audio Level patterns and Speech in Noise

    Time frame: From enrollment to the end of followup at 10 years

    Analysis will assess the speech recognition threshold and it's relationships with HAL at baseline and over the duration of the study

  5. Association between Headphone Audio Level patterns and tinnitus matching

    Time frame: From enrollment to the end of followup at 10 years

    At baseline and over the duration of the study

  6. Association between general health and individual characteristics and sound levels and/or audiometry tasks

    Time frame: From enrollment to the end of followup after 10 years

    Headphone Audio Levels will be assessed as the sound level and the audiometry tasks assessed will be Pure Tone Audiometry, Speech in Noise, and tinnitus matching

  7. Change from baseline to final audiometry

    Time frame: From enrollment to the end of followup after 10 years

    Including both Pure Tone Audiometry and Speech in Noise

  8. Change from baseline in abbreviated Pure Tone Audiometry following high headphone audio level notification

    Time frame: From enrollment to the end of followup after 10 years

    This comparison will occur for two frequencies (1 kHz and 4 kHz for both ears) within 24 hours of acute loud Headphone Audio Level exposure (LEQ equivalent to >97 dBA for >30 minutes)

  9. Headphone Audio Level association with baseline survey questions

    Time frame: From enrollment to the end of followup after 10 years

    This will includes questions about typical headphone us, typical environmental exposures, and hearing ability.

  10. Baseline Audiometry association with baseline survey questions

    Time frame: From enrollment to the end of followup after 10 years

    Baseline Audiometry includes both Pure Tone Audiometry and Speech in Noise. Survey questions include those regarding typical headphone use, typical environmental exposures, and hearing ability.

  11. Final Audiometry association with end-of-study survey questions

    Time frame: At the end of followup after 10 years

    Final Audiometry includes Pure Tone Audiometry and Speech in Noise. The end-of-study survey questions include typical headphone use, typical environmental exposures, and hearing ability.

  12. Change in survey questions

    Time frame: From enrollment to the end of followup after 10 years

    Survey questions regarding exposure changes over the course of the study

  13. Association between hearing ability and changes in hearing health and related health conditions

    Time frame: From enrollment to the end of followup after 10 years

    Hearing ability is evaluated both as perceived and evaluated. Changes in hearing health include audiometry and tinnitus. Related health conditions include items such as cognition, sleep, mental health, activity, mobility, and more.

  14. Descriptive assessment of participant use and experience

    Time frame: From enrollment to the end of followup after 10 years

    Experience with hearing related tools and device

Secondary outcomes

  1. Difference in Environmental Sound Level Patterns

    Time frame: From enrollment to the end of followup after 10 years

    Including sound pressure level and time at baseline and over the duration of the study. This outcome is only among participants that use Apple Watch.

  2. Association between Headphone Audio Levels and Environmental Sound Level patterns

    Time frame: From enrollment to the end of followup after 10 years

    This outcome is only among participants that use Apple Watch.

  3. Association between Environmental Sound Level patterns and Pure Tone Audiometry.

    Time frame: From enrollment to the end of followup after 10 years

    At baseline and over the duration of the study. This outcome is only among Participants that use Apple Watch.

  4. Association between Environmental Sound Level patterns and Speech in Noise

    Time frame: From enrollment to the end of followup after 10 years

    At baseline and over the duration of the study. This outcome is only among Participants that use Apple Watch.

  5. Association between Environmental Sound Level patterns and tinnitus matching task

    Time frame: From enrollment to the end of followup after 10 years

    At baseline and over the duration of the study. This outcome is only among Participants that use Apple Watch.

  6. Association between general health and personal characteristics and sound levels and hearing tasks

    Time frame: From enrollment to the end of followup after 10 years

    Sound levels include Environmental Sound Levels. Hearing tasks includes Pure Tone Audiometry, Speech in Noise, and Tinnitus matching. This outcome is only among Participants that use Apple Watch.

  7. Change from baseline in abbreviated Pure Tone Audiometry following loud environmental noise notification

    Time frame: From enrollment to the end of followup after 10 years

    This assessment will be for two frequencies (1 kHz and 4 kHz for both ears) tested within 24 hours of acute loud Environmental Sound Level exposure (LEQ equivalent to >97 dBA for >30 minutes). This outcome is only among Participants that use Apple Watch.

  8. Assess reported participant experience

    Time frame: From enrollment to the end of followup after 10 years

    Experience will be assessed via survey delivered with a notification after a prolonged loud environmental sound level exposure (LEQ equivalent to >80 dBA for >40 hours). This outcome is only among Participants that use Apple Watch.

  9. Association between heart rate measures and Headphone Audio Level patterns

    Time frame: From enrollment to the end of followup after 10 years

    This will include heart rate during activity (as assessed by logged Workouts and Active Energy trends by Watch). This outcome is only among participants that use Apple Watch.

  10. Association between heart rate measures and Environmental Sound Level patterns

    Time frame: From enrollment to the end of followup after 10 years

    This includes heart rate during activity (as assessed by logged Workouts and Active Energy trends by Watch). This outcome is only among participants that use Apple Watch.

Other outcomes

  1. Impact of hearing ability on other related aspects of health

    Time frame: From enrollment to the end of followup after 10 years

    Health includes things such as activity, cognition, mental health, mobility, sleep, health conditions, and health outcomes.

  2. Assess novel versions of hearing assessments

    Time frame: From enrollment to the end of followup after 10 years

    These assessments will be delivered using Research app. This may include different variations of speech in noise, pure tone audiometry, and related assessments such as evoked otoacoustic emissions (EOAE).

Sponsors and collaborators

Lead sponsor

Apple Inc.

Industry

Collaborators

  • World Health Organization

Registry information

Official study title

Apple Hearing Study: Characterization of Headphone Audio Levels, and Optional Wristwatch-Based Environmental Sound Levels, With Variable User Interface

Acronym: AHS

Important dates

Study start
2019
Primary completion
2029
Study completion
2029
First posted
Nov 21, 2019
Registry last updated
Mar 19, 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.

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