Shift Work DisorderNCT07702344
Circadian Rhythm and Health in Heavy Industry Shift Workers
An observational study of Shift Work Disorder and Shift Work Type Circadian Rhythm Sleep Disorder, run by Istanbul Gedik University at 1 site in Turkey (Türkiye).
Trial summary
Shift work can disrupt the body's circadian rhythm, which may negatively affect sleep, musculoskeletal health, and quality of life. Heavy industry workers who perform rotating or night shifts may be particularly vulnerable to these health problems. Read more about this study
- Who is it for?
- Ages 18 to 65 years
- Conditions the study is for
- Shift Work Disorder, Shift Work Type Circadian Rhythm Sleep Disorder
- What is being tested?
- Questionnaire-Based Assessment
- How many people
- 226 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 20 Jul 2026to 5 Oct 2026
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 65 years
- All sexes
- Adult, Older adult
Study population: Shift workers: Heavy industry workers employed in a shift work system will be recruited from participating industrial workplaces in İstanbul, Kocaeli in Türkiye. Eligible participants will be adults aged 18 to 65 years who have been working in a rotating or night shift schedule for at least 3 months and are willing to participate in the study.
Who may be able to join
- Ages 18-65
- Working in a shift system for at least 3 months
- Agreeing to participate in the work voluntarily
- Being a shift worker
Who cannot join
- Presence of using any medication that may affect alertness or muscle activity
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Investigation of Circadian Rhythm, Musculoskeletal Pain, Sleep Quality, and Quality of Life Among Heavy Industry Shift Workers: A Cross-Sectional Study
Shift work can disrupt the body's circadian rhythm, which may negatively affect sleep, musculoskeletal health, and quality of life. Heavy industry workers who perform rotating or night shifts may be particularly vulnerable to these health problems. This cross-sectional observational study will evaluate circadian rhythm characteristics, musculoskeletal pain, sleep quality, and quality of life among heavy industry shift workers. Participants will complete validated questionnaires assessing chronotype, musculoskeletal symptoms, sleep quality, and quality of life. The study will examine the associations between chronotype and these health outcomes and compare the results across different chronotype groups. The findings may contribute to a better understanding of the health effects of shift work and support the development of occupational health strategies for shift workers
- Being tested
- Questionnaire-Based Assessment
- Keywords
- Shift Work, Circadian Rhythm, Chronotype, Musculoskeletal pain, Sleeep quality, Quality of life, occupational health
- Medical subject headings
- Musculoskeletal Pain
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Questionnaire-Based AssessmentOther
Participants will complete validated self-administered questionnaires to assess chronotype, musculoskeletal pain, sleep quality, and quality of life. No therapeutic intervention will be administered.
| Study group | Role | What they receive |
|---|---|---|
| Heavy Industry Shift Workers | Heavy industry workers who perform shift work and will undergo a single questionnaire-based assessment. Receives: Other: Questionnaire-Based Assessment |
What is being measured
The primary outcome is the main question the study is designed to answer.
Morningness-Eveningness Questionnaire (MEQ)
The Morningness-Eveningness Questionnaire (MEQ) is a validated 19-item self-administered questionnaire used to determine an individual's chronotype (morning, intermediate, or evening type). Total scores range from 16 to 86. Higher scores indicate a greater preference for morningness, whereas lower scores indicate a greater preference for eveningness.
Measured: At enrollment (single assessment)
Secondary outcomes (3)
Cornell Musculoskeletal Discomfort Questionnaire (CMDQ)
The Cornell Musculoskeletal Discomfort Questionnaire (CMDQ) is a validated self-administered questionnaire used to assess the frequency, severity, and work-related impact of musculoskeletal discomfort in different body regions. The total score is calculated by summing weighted scores across body regions and does not have a fixed minimum or maximum value. Higher scores indicate greater musculoskeletal discomfort.
Measured: At enrollment (single assessment)
Pittsburgh Sleep Quality Index (PSQI)
The Pittsburgh Sleep Quality Index (PSQI) is a validated self-administered questionnaire used to evaluate sleep quality over the previous month. Total scores range from 0 to 21, with higher scores indicating poorer sleep quality.
Measured: At enrollment (single assessment)
World Health Organization Quality of Life-BREF (WHOQOL-BREF)
The World Health Organization Quality of Life-BREF (WHOQOL-BREF) is a validated self-administered questionnaire that assesses quality of life across the physical, psychological, social, and environmental domains. Domain scores are transformed to a 0-100 scale, with higher scores indicating better quality of life.
Measured: At enrollment (single assessment)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted14 Jul 2026
- Study start20 Jul 2026
- Primary completion5 Oct 2026
- Study completion5 Oct 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Shift Work DisorderStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Other
- Time perspective
- Cross-sectional
- Enrolment
- 226 participants (actual)
Sponsor and investigators
- Lead sponsor
- Istanbul Gedik University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Amine Ataç, Istanbul Gedik University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07702344
- Sponsor's protocol ID
- E-10840098-50.04-3312
- Status last verified
- Jul 2026
- First submitted
- 9 Jul 2026
- Last updated
- 7 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 7 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Investigation of Circadian Rhythm, Musculoskeletal Pain, Sleep Quality, and Quality of Life Among Heavy Industry Shift Workers: A Cross-Sectional Study
- ClinicalTrials.gov ID
- NCT07702344
- Acronym / sponsor ID
- E-10840098-50.04-3312
- Keywords
- Shift Work, Circadian Rhythm, Chronotype, Musculoskeletal pain, Sleeep quality, Quality of life, occupational health
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 226 participants (actual)
- Lead sponsor
- Istanbul Gedik UniversityUniversity, hospital or other
- Study start
- 20 Jul 2026 (actual)
- Primary completion
- 5 Oct 2026 (actual)
- Study completion
- 5 Oct 2026 (actual)
- First posted
- 14 Jul 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Shift work can disrupt the body's circadian rhythm, which may negatively affect sleep, musculoskeletal health, and quality of life. Heavy industry workers who perform rotating or night shifts may be particularly vulnerable to these health problems. This cross-sectional observational study will evaluate circadian rhythm characteristics, musculoskeletal pain, sleep quality, and quality of life among heavy industry shift workers. Participants will complete validated questionnaires assessing chronotype, musculoskeletal symptoms, sleep quality, and quality of life. The study will examine the associations between chronotype and these health outcomes and compare the results across different chronotype groups. The findings may contribute to a better understanding of the health effects of shift work and support the development of occupational health strategies for shift workers
Study design
- Observational model
- Other
- Time perspective
- Cross-sectional
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Heavy Industry Shift Workers | – | Other: Questionnaire-Based AssessmentHeavy industry workers who perform shift work and will undergo a single questionnaire-based assessment. |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Age groups
- Adult, Older adult
- Study population
- Shift workers: Heavy industry workers employed in a shift work system will be recruited from participating industrial workplaces in İstanbul, Kocaeli in Türkiye. Eligible participants will be adults aged 18 to 65 years who have been working in a rotating or night shift schedule for at least 3 months and are willing to participate in the study.
Key inclusion criteria (4 listed)
- Ages 18-65
- Working in a shift system for at least 3 months
- Agreeing to participate in the work voluntarily
- Being a shift worker
Key exclusion criteria (1 listed)
- Presence of using any medication that may affect alertness or muscle activity
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Questionnaire-Based AssessmentParticipants will complete validated self-administered questionnaires to assess chronotype, musculoskeletal pain, sleep quality, and quality of life. No therapeutic intervention will be administered. | Other | Heavy Industry Shift Workers |
Primary outcome
Morningness-Eveningness Questionnaire (MEQ)
Time frame: At enrollment (single assessment)
The Morningness-Eveningness Questionnaire (MEQ) is a validated 19-item self-administered questionnaire used to determine an individual's chronotype (morning, intermediate, or evening type). Total scores range from 16 to 86. Higher scores indicate a greater preference for morningness, whereas lower scores indicate a greater preference for eveningness.
3 secondary outcomes
Cornell Musculoskeletal Discomfort Questionnaire (CMDQ)
Time frame: At enrollment (single assessment)
Pittsburgh Sleep Quality Index (PSQI)
Time frame: At enrollment (single assessment)
World Health Organization Quality of Life-BREF (WHOQOL-BREF)
Time frame: At enrollment (single assessment)
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 7 Oct 2026.
- Individual participant dataSharing planned: Undecided
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Shift Work Disorder and Shift Work Type Circadian Rhythm Sleep Disorder, run by Istanbul Gedik University at 1 site in Turkey (Türkiye).
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 7 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Turkey (Türkiye). Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Morningness-Eveningness Questionnaire (MEQ) (time frame: At enrollment (single assessment)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 7 Oct 2026.