Recruiting

Light Exposure Interventions

Sponsor:

University of Arizona

Code:

NCT07391852

Conditions

Sleep Onset Latency

Eligibility Criteria

Sex: All

Age: 5 - 6

Healthy Volunteers: Not accepted

Interventions

Amber Tinted Glasses

Clear Glasses

Smart Lightbulbs

Study Details

Brief summary:

Many young children are exposed to light int he evening hours before bedtime. Children's biological clocks are highly sensitive to evening light exposure, which can delay the timing of the clock and make it harder to fall asleep. The purpose of this study is to test three strategies (adjustment to home lighting, amber-tinted glasses, clear glasses) to reduce evening light exposure in children ages 5-6 years with parent-reported sleep onset difficulties in order to improve their sleep and the timing of their biological clock. This study takes place over approximately 5 weeks. After baseline assessments of children's sleep timing, light exposure, cognition, and circadian rhythms, they will be randomly assigned to one of three interventions to reduce evening light exposure for two weeks. After the two-week intervention period, the baseline measures are repeated and parents are interviewed about their and their child's experiences with the intervention.

Conditions

Sleep Onset Latency

Study ID

NCT07391852

Start date

Jan 29, 2026

Status verified date

Jul, 2026

Completion date

Mar 31, 2030

Anticipated

Primary completion date

Dec 31, 2029

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 5 - 6

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • Inclusion requires that children are aged 5.0-6.9 years at the time of enrollment with a parent-reported sleep onset of ≥ 60 min after parents' desired bedtime at least three nights per week.

One adult parent of each participating child will also take part in the study. Parents must be able to provide consent for themselves and their child and to complete the interview at the end of the study.

Exclusion Criteria:

  • Children are excluded for the following reasons:

  • All sleep disorders as indicated on the telephone screener or by clinical cut-off scores on the Children's Sleep Habits Questionnaire (CSHQ), except for insomnia or DSWPD as features of these disorders are directly targeted by the intervention. Secondary analyses will explore if outcomes differ among participants with or without parent-reported symptoms consistent with these diagnoses.
  • Physical abilities that interfere with assessments (e.g., visual impairment), developmental disabilities (e.g., autism, attention-deficit/hyperactivity disorder (ADHD), pervasive developmental disorder), epilepsy or other neurological disorders, metabolic disorders, medical conditions that commonly require treatments or assessments during the night (e.g., cancer, diabetes, active asthma), current infection or lead poisoning; a head injury involving loss of consciousness in the past 6 months.
  • Current use of medications affecting daytime sleepiness, the circadian system, or light sensitivity.
  • Eye disorders or color blindness (determined with Ishihara Color Vision Test); corrected vision with eyeglasses is permitted.

Study Design

Enrollment

60 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Amber Tinted Glasses

Wearing "blue-blocker" glasses (lenses that filter out the blue portion of the visible spectrum) can reduce the melatonin suppression and alertness effects of evening light exposure in both adults and adolescents, as well as advance the timing of the circadian clock and sleep onset, compared with participants wearing placebo lenses. This intervention will examine their efficacy in advancing young children's sleep and circadian timing. Children will be given a pair of glasses (Block Blue Light), with amber-tinted lenses (advertised as blocking 100% of light from 380-550 nm. Children will wear the glasses starting 1 h before parent's selected bedtime each evening across the two-week intervention. Parents will also complete a daily diary detailing when the glasses are worn.

sham comparator: Clear Glasses

The sham comparator consists of the same protocols for the amber-tinted glasses, except that children will wear a pair of glasses with clear lenses (advertised as blocking 50% of light from 400-500 nm), which are significantly less effective at blocking short-wavelength light.

experimental: Smart Lightbulbs

The presence of more blue light in the home is associated with later circadian timing in both school-aged children and adults. This intervention will adjust the evening home lighting environment to be less stimulating to children's circadian clocks. Smart light bulbs (dimmable and color tunable LED bulbs) will be installed in participants' homes light fixtures, or in the child's bedroom, bathroom, as well as areas the child is likely to spend time in after dinner (i.e., living room, playroom). The researchers will program the lights to transition to a lower CCT and dimmer intensity to achieve the recommended evening mEDI of 10 lux starting 1 h before the child's parent-selected bedtime.

Interventions

Amber Tinted Glasses

Children will wear amber-tinted glasses in the evening hours before bedtime to reduce exposure to short-wavelength (blue) light. The glasses are intended to reduce circadian disruption associated with evening light exposure.

Clear Glasses

Children will wear clear glasses in the evening hours before bedtime. This sham intervention controls for wearing glasses without reducing light exposure.

Smart Lightbulbs

Smart light bulbs will be installed in the child's home and programmed to reduce short-wavelength light exposure during evening hours before bedtime.

Primary outcome measure

  • Intervention Feasibility [ Time Frame: Throughout the two-week intervention period. ]
  • Acceptability [ Time Frame: Week 5 ]

Central Contacts and Locations

Central contacts

Lauren E Hartstein, PhD

520-621-1360laurenhartstein@arizona.edu

Locations

University of Arizona

Recruiting

Tucson, Arizona, United States, 85724

Contacts

Lauren E Hartstein, PhD

520-621-1360laurenhartstein@arizona.edu

More Information

Sponsor

University of Arizona

Last update posted

Oct 14, 2026

Last verified

Jul, 2026

Keywords

  • Behavioral sleep problems
  • Circadian phase
  • sleep onset latency
  • Early childhood
  • dim light melatonin onset (DLMO)
  • Evening light exposure
  • Light intervention

Trial information was received from ClinicalTrials.gov and was last updated on 2026-10-15. This information was provided to ClinicalTrials.gov by University of Arizona on 2026-10-14. Recruitment status is synced daily from ClinicalTrials.gov and may not reflect the sponsor's current status. Confirm during your call.