SmokingNCT03968900
Racial Differences in Circadian and Sleep Mechanisms for Nicotine Dependence, Craving, and Withdrawal
A study testing Sleep restriction condition and Sleep extension condition in people with Smoking and Sleep Disturbance, run by University of Alabama at Birmingham at 1 site in United States.
Trial summary
The number one preventable cause of death in the world is tobacco use. Cigarette smoking in particular, costs an estimated $300 billion due to expenses related to medical care and lost productivity. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Smoking, Sleep Disturbance, Nicotine Dependence
- What is being tested?
- Sleep restriction condition and Sleep extension condition
- Type of treatment
- Lifestyle or therapy programme
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 29 participants
- Where
- 1 siteUnited States
- Study dates
- 1 Jan 2021to 1 Apr 2025
- Phase
- Interventional
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
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 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 18 years or older
- Able to read and speak English
- Non-Hispanic African American (Black) or non-Hispanic white race
- Daily smoker (5 or more cigarettes a day for the past one year and having smoked more than 100 cigarettes in lifetime) or non-smoker (smoked fewer than 100 cigarettes in a lifetime and no smoking-not even a puff- in the last year)
- Currently residing in Alabama
- 18 years or older
Show all 15Show fewer
- Able to read and speak English
- Non-Hispanic African American (Black) or non-Hispanic white race
- Daily smoker defined as smoking 5 or more cigarettes a day for the past one year and having smoked more than 100 cigarettes in lifetime, as well as by an expired Carbon Monoxide (CO )cut-off of Carbon Monoxide (CO)>10ppm and positive cotinine test to ensure daily smoking OR non-smoker defined as smoking fewer than 100 cigarettes in a lifetime and no smoking-not even a puff- in the last year, as well as by an expired Carbon monoxide (CO) cut-off of Carbon Monoxide (CO)<3 ppm and negative cotinine test.
- Currently residing in Alabama
- 18 years or older
- Able to read and speak English
- Non-Hispanic African American (Black) or non-Hispanic white race
- Daily smoker defined as smoking 5 or more cigarettes a day for the past one year and having smoked more than 100 cigarettes in lifetime, as well as by an expired Carbon Monoxide (CO) cut-off of Carbon Monoxide (CO)>10ppm and positive cotinine test to ensure daily smoking
- Currently residing in Alabama
Who cannot join
- Non-English speaking
- Lives in restricted environment that does not allow smoking
- Pregnant or lactating
- Daily or exclusive use of other tobacco products (e.g., cigars, e-cigarettes) if a smoker; if non-smoker, any other tobacco product use is exclusionary
- Currently receiving smoking cessation treatment or using electronic cigarettes or other tobacco to try and quit smoking cigarettes
- Participants would work outside normal 7 a.m. to 6 p.m. hours
Show all 38Show fewer
- Former smokers
- Sub-study 2
- Non-English speaking
- Lives in restricted environment that does not allow smoking
- Pregnant or lactating
- Testing positive on urine drug screen test at baseline - any drugs other than Tetrahydrocannabinol (THC) not allowed
- Daily or exclusive use of other tobacco products (e.g., cigars, e-cigarettes) if a smoker; if non-smoker, any other tobacco product use is exclusionary
- Currently receiving smoking cessation treatment or using electronic cigarettes or other tobacco to try and quit smoking cigarettes
- Participants would work outside normal 7 a.m. to 6 p.m. hours
- Former smokers
- History of a medical condition (e.g., bipolar disorder, migraine, or seizure disorder) that might be exacerbated by sleep deprivation as a result of Study 3
- History of a serious lung/breathing disease that prevents one from walking or holding their breath for 10 seconds (in order to complete Carbon Monoxide breath test)
- Cognitive impairment such that participant is unable to provide informed consent
- Acutely suicidal, manic, acutely intoxicated, or otherwise not stable enough to provide informed consent
- Living outside of the Birmingham metro area (> 20 miles away from University of Alabama at Birmingham Main Campus)
- Sub-study 3
- Non-English speaking
- Lives in restricted environment that does not allow smoking
- Pregnant or lactating
- Daily or exclusive use of other tobacco products (e.g., cigars, e-cigarettes) if a smoker; if non-smoker, any other tobacco product use is exclusionary
- Currently receiving smoking cessation treatment or using electronic cigarettes or other tobacco to try and quit smoking cigarettes
- Participants would work outside normal 7 a.m. to 6 p.m. hours
- Former smokers
- History of a medical condition (e.g., bipolar disorder, migraine, or seizure disorder) that might be exacerbated by sleep deprivation as a result of Study 3
- Currently taking any psychiatric medications, pain medications (i.e., opioids), or sleep medications (e.g., Ambien, trazodone, melatonin pills, Cannabidiol (CBD) products)
- History of a serious lung/breathing disease that prevents one from walking or holding their breath for 10 seconds
- Testing positive on urine drug screen test at baseline - any drugs other than Tetrahydrocannabinol (THC) not allowed
- Has an apnea-hypopnea index (AHI) score of > 15 on home sleep testing that was conducted during sub-study 2
- Uses Continuous positive airway pressure (CPAP) machine to sleep at night
- Cognitive impairment such that participant is unable to provide informed consent
- Acutely suicidal, manic, acutely intoxicated, or otherwise not stable enough to provide informed consent
- Living outside of the Birmingham metro area (> 20 miles away from University of Alabama at Birmingham Main Campus)
Trial locations and contacts
1 site in 1 country.
United States1 site
University of Alabama, Birmingham
Birmingham, Alabama, 35226
About this study
The number one preventable cause of death in the world is tobacco use. Cigarette smoking in particular, costs an estimated $300 billion due to expenses related to medical care and lost productivity. Despite similar smoking prevalence rates, blacks suffer disproportionately from smoking-related harms compared to whites.Sleep disparities such as shortened sleep duration, shorter circadian periodicity, earlier chronotype, and increased variability of sleep timing have been reported more frequently in blacks compared to whites. Given that poor sleep quality predicts relapse from smoking cessation programs, particularly among socioeconomically disadvantaged adults, sleep deficiencies and irregular timing of sleep may impact smoking craving and withdrawal symptoms over the course of the 24-hour day. Surprisingly, few studies have examined these temporal patterns of smoking and craving, and none with regard to sleep disruption, chronotype or racial disparities. A better understanding of these factors may explain heterogeneity within the smoking population, especially in minorities. Thus, the purpose of this proposal is to test the central hypothesis that the impact of chronotype and impaired sleep on cigarette usage as well as smoking dependence, urge/craving, and withdrawal depends on race.
Read the detailed description
Three specific aims will determine: contributions of sleep timing and sleep quality and quantity to racial disparities in smoking status (Aim 1), objective sleep characteristics and smoking behavior among blacks and whites who smoke cigarettes (Aim 2), and whether sleep restriction modifies craving and withdrawal in racially diverse smokers (Aim 3). Specifically, we will utilize self-report questionnaires, objective measures of sleep quality and timing (actigraphy) and circadian phase (dim light melatonin onset), as well as ecological momentary assessment of cigarette use, smoking urges, cravings, and withdrawal symptoms to identify circadian and sleep characteristics that are most strongly associated with smoking status, heaviness of smoking and dependence among blacks and whites. Finally, we will test whether acute sleep restriction (4 hours of time-in-bed) versus sleep extension (10 hours of time-in-bed) modifies craving and withdrawal symptoms following cessation in black and white smokers. If successful, the results of this study will result in identification of circadian dysfunction and insufficient sleep as mechanisms that underlie the association between sleep and cigarette smoking behaviors and dependence in diverse populations. Moreover, these findings are likely to inform clinicians of the importance of sleep and sleep timing on cigarette smoking behaviors and dependence that will help in the development of novel interventions to reduce morbidity and mortality caused by tobacco use.
- Conditions
- Smoking, Sleep Disturbance, Nicotine Dependence
- Being tested
- Sleep restriction condition, Sleep extension condition
- Keywords
- smoking, sleep deficiencies, socioeconomic disadvantage, Race
- Medical subject headings
- Smoking, Parasomnias, Tobacco Use Disorder
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Sleep restriction conditionBehavioural
On day 1, participants will complete study assessments and will be fitted with an Actiwatch and instructed to continue a fixed time in bed (8 hours duration with no more than 20 min deviation) centered on habitual sleep (e.g., 11:00 p.m. to 7:00 a.m.). Naps will not be allowed. Following the one-week baseline sleep stabilization, participants will engage in the sleep restriction condition (4 hours, TIB [Time in Bed]; 1:00 a.m. to 5:00 a.m.). On the day of each sleep study, participants will be admitted to University of Alabama Birmingham (UAB) Highlands Hospital sleep unit at 7:00 p.m. and do an initial CO breathe test and fill out study questionnaires and a timeline follow-back procedure Participants will monitored for smoking withdrawal. Every 2 hours, participants to fill out various questionnaires. Participants will repeat the same conditions as the first night. After a two-week washout, participants will be crossed over to the alternate sleep extension/restriction condition.
Sleep extension conditionBehavioural
sleep extension On day 1, participants will complete study assessments and will be fitted with an Actiwatch and instructed to continue a fixed time in bed (8 hours duration with no more than 20 min deviation) centered on habitual sleep (e.g., 11:00 p.m. to 7:00 a.m.). Naps will not be allowed. Following the one-week baseline sleep stabilization, participants will engage in the sleep extension condition (10 hours, (TIB); 10:00 p.m. to 8:00 a.m.). On the day of each sleep study, participants will be admitted to University of Alabama Birmingham Highlands Hospital sleep unit at 7:00 p.m. and do an initial CO breathe test and fill out study questionnaires and a timeline follow-back procedure Participants will monitored for smoking withdrawal. Every 2 hours, participants to fill out various questionnaires. Participants will repeat the same conditions as the first night. After a two-week washout, participants will be crossed over to the alternate sleep extension/restriction condition.
| Study group | Role | What they receive |
|---|---|---|
| Sleep Restriction | Experimental | 4 hours time in bed (1 am to 5 am) Receives: Behavioral: Sleep restriction condition |
| Sleep Extension | Experimental | 10 hours time in bed (10 pm to 8 am) Receives: Behavioral: Sleep extension condition |
What is being measured
The primary outcome is the main question the study is designed to answer.
Sleep Hygiene Index
A 13-item scale that assesses behaviors, such as variability in wake-time, timing of physical activity, and substance use, that comprise sleep hygiene. Higher values indicate worse sleep hygiene. The minimum value is 0, and the maximum value is 52.
Measured: 1 day at baseline before either intervention
Secondary outcomes (9)
Pittsburgh Sleep Quality Index
A 7-item self-report measure that assesses global sleep quality over the past month. Additionally, sub-scales that include duration of sleep, sleep disturbance, sleep latency, daytime dysfunction, sleep efficiency, and dependence on hypnotic medication may be calculated from individual items. Higher scores indicate worse sleep quality. The minimum score is 0, and the maximum score is 21.
Measured: 1 day at baseline before either intervention
Munich Chronotype Questionnaire
Questionnaire that determines chronotype from midsleep time calculated from sleep onset and offset on both free days and work days. Chronotype will be determined from the mid-sleep time on days off. Specifically, Mid-sleep time is equal to Sleep onset + Sleep duration/2. For those who sleep longer on days off than on workdays, we will correct for weekend recovery sleep by subtracting 'sleep debt' accumulated, which is estimated by the following equation: Sleep duration on free days - Sleep duration (average) for the week/2. Chronotype is the participant's midsleep time on free days. Higher values indicate that midsleep time is later in the day. The minimum value is 0, and the maximum value is 24.
Measured: 1 day at baseline before either intervention
Fagerström Test for Nicotine Dependence
A 6-item self-report measure of nicotine dependence derived from the Fagerström Tolerance Questionnaire. Higher scores indicate greater nicotine dependence. The minimum value is 1, and the maximum value is 10.
Measured: 1 day at baseline before either intervention
Snoring History, Tired During the Day, Observed Stop Breathing While Sleep, High Blood Pressure, BMI More Than 35 kg/m2, Age More Than 50 Years, Neck Circumference More Than 40 cm and Male Gender (STOP-BANG) Questionnaire
A 8-item self-report questionnaire that assesses the primary risk factors for obstructive sleep apnea to create a total score that ranges from 0 to 8. Higher scores indicate greater risk of sleep apnea.
Measured: 1 day at baseline before either intervention
Insomnia Severity Index
A 7-item self-report questionnaire that assesses the severity of core symptoms of insomnia over the previous 2 weeks. Higher scores indicate more severe insomnia. The minimum score is 0, and the maximum score is 28.
Measured: 1 day at baseline before either intervention
Dysfunctional Beliefs and Attitudes About Sleep (DBAS)
A 16-item questionnaire that assesses beliefs about sleep and the consequences of poor sleep. Higher scores indicate more dysfunctional beliefs about sleep. The minimum score is 0, and the maximum score is 10.
Measured: 1 day at baseline before either intervention
Epworth Sleepiness Scale (ESS)
A 8-item questionnaire that asks individuals to rate their "chances of dozing off" on a scale of 0 (never) to 3 (high) in eight different situations. The scores are summed to create a total score with higher values indicating higher chances of dozing off. The minimum score is 0, and the maximum score is 24.
Measured: 1 day at baseline before either intervention
Everyday Discrimination Scale (EDS)
This 9-item assessment queries about experiences of discrimination such as being treated less respectfully or people thinking that you are dishonest. Responses range from "almost every day" to "never." Higher score indicate more ways that discrimination was experienced. The minimum score is 0, and the maximum score is 9.
Measured: 1 day at baseline before either intervention
Perceived Stress Scale - 10 Item (PSS-10)
Self-report questionnaire that assesses a person's perceived stress with a 5-point Likert scale ranging from "Never" to "Very Often." Higher scores indicate greater levels of perceived stress. The minimum score is 0, and the maximum score is 40.
Measured: 1 day at baseline before either intervention
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted30 May 2019
- Study start1 Jan 2021
- Primary completion1 Apr 2025
- Study completion1 Apr 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Other trials for SmokingStudies of the same condition, open and under way.
- More trials run by University of Alabama at BirminghamThe sponsor's other registered studies.
- 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
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Enrolment
- 29 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Alabama at Birmingham
- Sponsor type
- University, hospital or other
- Collaborators
- University of Oklahoma, National Institute on Drug Abuse (NIDA)
- Responsible party
- Principal investigator, Karen Cropsey, University of Alabama at Birmingham
- Investigators
- Karen L Cropsey, Psy.D., Principal investigator, University of Alabama at Birmingham
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03968900
- Sponsor's protocol ID
- 1288803
- Other IDs
- R01DA046096
- Status last verified
- Apr 2026
- First submitted
- 23 May 2019
- Last updated
- 25 Aug 2026
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 25 Aug 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Racial Differences in Circadian and Sleep Mechanisms for Nicotine Dependence, Craving, and Withdrawal
- ClinicalTrials.gov ID
- NCT03968900
- Acronym / sponsor ID
- 1288803
- Conditions
- Smoking, Sleep Disturbance, Nicotine Dependence
- Keywords
- smoking, sleep deficiencies, socioeconomic disadvantage, Race
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 29 participants (actual)
- Lead sponsor
- University of Alabama at BirminghamUniversity, hospital or other
- Collaborators
- University of Oklahoma, National Institute on Drug Abuse (NIDA)
- Study start
- 1 Jan 2021 (actual)
- Primary completion
- 1 Apr 2025 (actual)
- Study completion
- 1 Apr 2025 (actual)
- First posted
- 30 May 2019 (actual)
- Results
- Posted 31 Jul 2026
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The number one preventable cause of death in the world is tobacco use. Cigarette smoking in particular, costs an estimated $300 billion due to expenses related to medical care and lost productivity. Despite similar smoking prevalence rates, blacks suffer disproportionately from smoking-related harms compared to whites.Sleep disparities such as shortened sleep duration, shorter circadian periodicity, earlier chronotype, and increased variability of sleep timing have been reported more frequently in blacks compared to whites. Given that poor sleep quality predicts relapse from smoking cessation programs, particularly among socioeconomically disadvantaged adults, sleep deficiencies and irregular timing of sleep may impact smoking craving and withdrawal symptoms over the course of the 24-hour day. Surprisingly, few studies have examined these temporal patterns of smoking and craving, and none with regard to sleep disruption, chronotype or racial disparities. A better understanding of these factors may explain heterogeneity within the smoking population, especially in minorities. Thus, the purpose of this proposal is to test the central hypothesis that the impact of chronotype and impaired sleep on cigarette usage as well as smoking dependence, urge/craving, and withdrawal depends on race.
Detailed description
Three specific aims will determine: contributions of sleep timing and sleep quality and quantity to racial disparities in smoking status (Aim 1), objective sleep characteristics and smoking behavior among blacks and whites who smoke cigarettes (Aim 2), and whether sleep restriction modifies craving and withdrawal in racially diverse smokers (Aim 3). Specifically, we will utilize self-report questionnaires, objective measures of sleep quality and timing (actigraphy) and circadian phase (dim light melatonin onset), as well as ecological momentary assessment of cigarette use, smoking urges, cravings, and withdrawal symptoms to identify circadian and sleep characteristics that are most strongly associated with smoking status, heaviness of smoking and dependence among blacks and whites. Finally, we will test whether acute sleep restriction (4 hours of time-in-bed) versus sleep extension (10 hours of time-in-bed) modifies craving and withdrawal symptoms following cessation in black and white smokers. If successful, the results of this study will result in identification of circadian dysfunction and insufficient sleep as mechanisms that underlie the association between sleep and cigarette smoking behaviors and dependence in diverse populations. Moreover, these findings are likely to inform clinicians of the importance of sleep and sleep timing on cigarette smoking behaviors and dependence that will help in the development of novel interventions to reduce morbidity and mortality caused by tobacco use.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Sleep Restriction | Experimental | Behavioral: Sleep restriction condition4 hours time in bed (1 am to 5 am) |
| Sleep Extension | Experimental | Behavioral: Sleep extension condition10 hours time in bed (10 pm to 8 am) |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (15 listed)
- 18 years or older
- Able to read and speak English
- Non-Hispanic African American (Black) or non-Hispanic white race
- Daily smoker (5 or more cigarettes a day for the past one year and having smoked more than 100 cigarettes in lifetime) or non-smoker (smoked fewer than 100 cigarettes in a lifetime and no smoking-not even a puff- in the last year)
- Currently residing in Alabama
Key exclusion criteria (38 listed)
- Non-English speaking
- Lives in restricted environment that does not allow smoking
- Pregnant or lactating
- Daily or exclusive use of other tobacco products (e.g., cigars, e-cigarettes) if a smoker; if non-smoker, any other tobacco product use is exclusionary
- Currently receiving smoking cessation treatment or using electronic cigarettes or other tobacco to try and quit smoking cigarettes
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 |
|---|---|---|
| Sleep restriction conditionOn day 1, participants will complete study assessments and will be fitted with an Actiwatch and instructed to continue a fixed time in bed (8 hours duration with no more than 20 min deviation) centered on habitual sleep (e.g., 11:00 p.m. to 7:00 a.m.). Naps will not be allowed. Following the one-week baseline sleep stabilization, participants will engage in the sleep restriction condition (4 hours, TIB [Time in Bed]; 1:00 a.m. to 5:00 a.m.). On the day of each sleep study, participants will be admitted to University of Alabama Birmingham (UAB) Highlands Hospital sleep unit at 7:00 p.m. and do an initial CO breathe test and fill out study questionnaires and a timeline follow-back procedure Participants will monitored for smoking withdrawal. Every 2 hours, participants to fill out various questionnaires. Participants will repeat the same conditions as the first night. After a two-week washout, participants will be crossed over to the alternate sleep extension/restriction condition. | Behavioural | Sleep Restriction |
| Sleep extension conditionsleep extension On day 1, participants will complete study assessments and will be fitted with an Actiwatch and instructed to continue a fixed time in bed (8 hours duration with no more than 20 min deviation) centered on habitual sleep (e.g., 11:00 p.m. to 7:00 a.m.). Naps will not be allowed. Following the one-week baseline sleep stabilization, participants will engage in the sleep extension condition (10 hours, (TIB); 10:00 p.m. to 8:00 a.m.). On the day of each sleep study, participants will be admitted to University of Alabama Birmingham Highlands Hospital sleep unit at 7:00 p.m. and do an initial CO breathe test and fill out study questionnaires and a timeline follow-back procedure Participants will monitored for smoking withdrawal. Every 2 hours, participants to fill out various questionnaires. Participants will repeat the same conditions as the first night. After a two-week washout, participants will be crossed over to the alternate sleep extension/restriction condition. | Behavioural | Sleep Extension |
Primary outcome
Sleep Hygiene Index
Time frame: 1 day at baseline before either intervention
A 13-item scale that assesses behaviors, such as variability in wake-time, timing of physical activity, and substance use, that comprise sleep hygiene. Higher values indicate worse sleep hygiene. The minimum value is 0, and the maximum value is 52.
9 secondary outcomes
Pittsburgh Sleep Quality Index
Time frame: 1 day at baseline before either intervention
Munich Chronotype Questionnaire
Time frame: 1 day at baseline before either intervention
Fagerström Test for Nicotine Dependence
Time frame: 1 day at baseline before either intervention
Snoring History, Tired During the Day, Observed Stop Breathing While Sleep, High Blood Pressure, BMI More Than 35 kg/m2, Age More Than 50 Years, Neck Circumference More Than 40 cm and Male Gender (STOP-BANG) Questionnaire
Time frame: 1 day at baseline before either intervention
Insomnia Severity Index
Time frame: 1 day at baseline before either intervention
Dysfunctional Beliefs and Attitudes About Sleep (DBAS)
Time frame: 1 day at baseline before either intervention
Epworth Sleepiness Scale (ESS)
Time frame: 1 day at baseline before either intervention
Everyday Discrimination Scale (EDS)
Time frame: 1 day at baseline before either intervention
Perceived Stress Scale - 10 Item (PSS-10)
Time frame: 1 day at baseline before either intervention
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 25 Aug 2026.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
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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.
Karen L Cropsey, Psy.D. principal investigator
University of Alabama at Birmingham
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Sleep restriction condition and Sleep extension condition in people with Smoking and Sleep Disturbance, run by University of Alabama at Birmingham at 1 site in United States.
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 15 inclusion and 38 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 25 Aug 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 United States. 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?
Yes. Results are posted in the registry (first posted 31 Jul 2026). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
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?
Sleep Hygiene Index (time frame: 1 day at baseline before either intervention). 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 25 Aug 2026.