Light Therapy for University Students

NCT07659171 | Completed

• 1 other identifier: VSN-19054
• Study Type: interventional
• Target: 39
• Locations: 1 country
• Sites: 1

Brief Summary

The effects of light therapy on well-being among university students was investigated. A three-week intervention study examined whether the use of light glasses improved sleep quality and concentration and reduced symptoms of depression and anxiety among university students. First, a questionnaire was administered to about 130 students to screen for sleep problems. Based on the responses, those with the most sleep problems were invited to participate in the intervention study, which resulted in 39 participants in total. Although studies of light therapy for sleep problems and depression among patients have yielded positive results, the use of light has not been studied much among healthy individuals. The intervention study used glasses that project light in two intensities and participants were randomized into two groups with different intensities of light. The aim of the study was to: a) compare the effects of different light intensities on sleep and concentration and b) investigate whether light therapy influences symptoms of depression and anxiety among university students. The study is expected to increase knowledge of light therapy among healthy individuals, and if the treatment proves successful, it is an easy and inexpensive way to increase well-being among university students.

Conditions

University Students; Sleep Problems; Well-being; Concentration Performance; Depression and Anxiety Symptom

Keywords

University students; Young adults; Light therapy; Sleep; Well-being; Intervention

Outcome Measures

Primary Outcomes (10)

• The Bergen Insomnia Scale (BIS)

  The Bergen Insomnia Scale (BIS) is a short scale on sleep habits consisting of six items pertaining to sleep onset, maintenance, early morning wakening, restorative sleep, daytime functioning, and sleep satisfaction. Responses indicate how often sleep problems, according to the six items, are experienced during the last month on an 8-point scale (0-7 days per week) with a range between 0 and 42, where a higher score suggests more sleep problems.

  BIS was used to screen for sleep-related problems, prior to the intervention, at baseline (day 1), at the middle of intervention (FU1, day 11) and at the of intervention (FU2, day 21).

• The Pittsburgh Sleep Quality Index (PSQI)

  The Pittsburgh Sleep Quality Index (PSQI) consists of 19 self-rated items about sleep habits during the last month. The questions are categorised into seven components, rated from 0 to 3, evaluating sleep duration, quality, and latency as well as habitual sleep efficiency, sleep disturbances, usage of sleep medication, and daytime dysfunction. A global PSQI score, ranging from 0 to 21, is calculated by summarising the seven components' scores, where a higher global score indicates worse sleep quality and a score above five suggests poor sleep quality.

  PSQI was administered at baseline (day 1), FU1 (day 11), and FU2 (day 21).

• Objective sleep measure by actigraphy: Total time in bed

  Wrist-worn actigraphy devices (model GT3X+ ActiSleep) were used to objectively measure sleep. Sleep parameters were calculated using the Cole-Kripke sleep algorithm in the ActiLife 6 data analysis software. Parameter measured: Total time in bed, measured as minutes.

  Participants were asked to wear the devices on their non-dominant arm for four consecutive days, both at baseline (day 1-4) and at FU2 (day 18-21).

• Objective sleep measure by actigraphy: Total sleep time

  Wrist-worn actigraphy devices (model GT3X+ ActiSleep) were used to objectively measure sleep. Sleep parameters were calculated using the Cole-Kripke sleep algorithm in the ActiLife 6 data analysis software. Parameter measured: Total sleep time, measured as minutes.

  Participants were asked to wear the devices on their non-dominant arm for four consecutive days, both at baseline (day 1-4) and at FU2 (day 18-21).

• Objective sleep measure by actigraphy: Sleep latency

  Wrist-worn actigraphy devices (model GT3X+ ActiSleep) were used to objectively measure sleep. Sleep parameters were calculated using the Cole-Kripke sleep algorithm in the ActiLife 6 data analysis software. Parameter measured: Sleep latency, measured as minutes.

  Participants were asked to wear the devices on their non-dominant arm for four consecutive days, both at baseline (day 1-4) and at FU2 (day 18-21).

• Objective sleep measure by actigraphy: Wake after sleep onset

  Wrist-worn actigraphy devices (model GT3X+ ActiSleep) were used to objectively measure sleep. Sleep parameters were calculated using the Cole-Kripke sleep algorithm in the ActiLife 6 data analysis software. Parameter measured: Wake after sleep onset, measured as minutes.

  Participants were asked to wear the devices on their non-dominant arm for four consecutive days, both at baseline (day 1-4) and at FU2 (day 18-21).

• Objective sleep measure by actigraphy: Number of awakenings

  Wrist-worn actigraphy devices (model GT3X+ ActiSleep) were used to objectively measure sleep. Sleep parameters were calculated using the Cole-Kripke sleep algorithm in the ActiLife 6 data analysis software. Parameter measured: Number of awakenings, measured as number of awakenings per sleep period.

  Participants were asked to wear the devices on their non-dominant arm for four consecutive days, both at baseline (day 1-4) and at FU2 (day 18-21).

• Objective sleep measure by actigraphy: Sleep fragmentation index

  Wrist-worn actigraphy devices (model GT3X+ ActiSleep) were used to objectively measure sleep. Sleep parameters were calculated using the Cole-Kripke sleep algorithm in the ActiLife 6 data analysis software. Parameter measured: Sleep fragmentation index, measured as percentage.

  Participants were asked to wear the devices on their non-dominant arm for four consecutive days, both at baseline (day 1-4) and at FU2 (day 18-21).

• Objective sleep measure by actigraphy: Sleep movement index

  Wrist-worn actigraphy devices (model GT3X+ ActiSleep) were used to objectively measure sleep. Sleep parameters were calculated using the Cole-Kripke sleep algorithm in the ActiLife 6 data analysis software. Parameter measured: Sleep movement index, measured as events per hour.

  Participants were asked to wear the devices on their non-dominant arm for four consecutive days, both at baseline (day 1-4) and at FU2 (day 18-21).

• Objective sleep measure by actigraphy: Sleep efficiency

  Wrist-worn actigraphy devices (model GT3X+ ActiSleep) were used to objectively measure sleep. Sleep parameters were calculated using the Cole-Kripke sleep algorithm in the ActiLife 6 data analysis software. Parameter measured: Sleep efficiency, measured as percentage.

  Participants were asked to wear the devices on their non-dominant arm for four consecutive days, both at baseline (day 1-4) and at FU2 (day 18-21).

Secondary Outcomes (7)

• The Center for Epidemiological Studies Depression Scale (CES-D)

  CES-D was administered at baseline (day 1), FU1 (day 11) and FU2 (day 21).

• General Anxiety Disorder (GAD-7)

  GAD-7 was administered at baseline (day 1), FU1 (day 11) and FU2 (day 21).

• The reduced Horne & Östberg Morningness-Eveningness Questionnaire (rMEQ)

  rMEQ was administered at baseline (day 1).

• The Epworth Sleepiness Scale (ESS)

  ESS was administered at baseline (day 1), FU1 (day 11) and FU2 (day 21).

• Objective measures of cognitive performance: Operation Span (Ospan)

  Ospan was administered at baseline (day 1) and FU2 (day 21).

Study Arms (2)

Blue Light Therapy

EXPERIMENTAL

Exposure of experimental circadian-effective blue light (BL) by glasses for 30 minutes each morning during the 3-week intervention

Device: Light Glasses (Experimental)

Dim Light Therapy

ACTIVE COMPARATOR

Exposure of experimental comparison circadian-ineffective dim light (DL) by glasses for 30 minutes each morning during the 3-week intervention

Device: Light Glasses (Comparison)

Interventions

Light Glasses (Experimental) DEVICE

The circadian-effective light glasses used by the experimental group (BL) emitted narrowband (peak lambda = 470 nm) blue light with an irradiance of 250 μW/cm2 (120 lux). The light glasses emit light from LEDs at a distance of 15 millimeters (15mm, 0.015.) from the eye. The device is classified as safe for the eyes in accordance with the international standard IEC 62471 and complies with the United States of America's FCC marking, and is designed to be worn on the participant's head, similar to a pair of regular glasses. For safety purposes, the light glasses do not contain UV or infra-red light. Brand: AYO glasses.

Blue Light Therapy

Light Glasses (Comparison) DEVICE

The circadian-ineffective sham glasses (DL) emitted blue light with an irradiance of 2.5 μW/cm2 (1.16 lux). The light glasses emit light from LEDs at a distance of 15 millimeters (15mm, 0.015.) from the eye. The device is classified as safe for the eyes in accordance with the international standard IEC 62471 and complies with the United States of America's FCC marking, and is designed to be worn on the participant's head, similar to a pair of regular glasses. For safety purposes, the light glasses do not contain UV or infra-red light. Brand: AYO glasses.

Dim Light Therapy

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Being a psychology student at Reykjavik University, Iceland
• Able to understand, read and write Icelandic
• At screening assessment prior to the intervention, demonstrating a score of three or above on any of the six items of the BIS scale, thereby including students who showed even mild symptoms of sleep problems

You may not qualify if:

• Not being a psychology student at Reykjavik University, Iceland
• Not able to understand, read and write Icelandic
• Demonstrating a score below three on all of the six items of the BIS scale

Sponsors & Collaborators

• Reykjavik University: lead
• The Icelandic Research Fund: collaborator

Study Sites (1)

Department of Psychology, Reykjavík University

Reykjavik, 102, Iceland

Location

Related Publications (6)

• Danielsson K, Sakarya A, Jansson-Frojmark M. The reduced Morningness-Eveningness Questionnaire: Psychometric properties and related factors in a young Swedish population. Chronobiol Int. 2019 Apr;36(4):530-540. doi: 10.1080/07420528.2018.1564322. Epub 2019 Jan 7.

  PMID: 30614272 BACKGROUND

• Radloff, L. S. (1977). The CES-D Scale: A Self-Report Depression Scale for Research in the General Population. Applied Psychological Measurement, 1(3), 385-401. doi:10.1177/014662167700100306

  BACKGROUND

• Johns MW. A new method for measuring daytime sleepiness: the Epworth sleepiness scale. Sleep. 1991 Dec;14(6):540-5. doi: 10.1093/sleep/14.6.540.

  PMID: 1798888 BACKGROUND

• Spitzer RL, Kroenke K, Williams JB, Lowe B. A brief measure for assessing generalized anxiety disorder: the GAD-7. Arch Intern Med. 2006 May 22;166(10):1092-7. doi: 10.1001/archinte.166.10.1092.

  PMID: 16717171 BACKGROUND

• Buysse DJ, Reynolds CF 3rd, Monk TH, Berman SR, Kupfer DJ. The Pittsburgh Sleep Quality Index: a new instrument for psychiatric practice and research. Psychiatry Res. 1989 May;28(2):193-213. doi: 10.1016/0165-1781(89)90047-4.

  PMID: 2748771 BACKGROUND

• Pallesen S, Bjorvatn B, Nordhus IH, Sivertsen B, Hjornevik M, Morin CM. A new scale for measuring insomnia: the Bergen Insomnia Scale. Percept Mot Skills. 2008 Dec;107(3):691-706. doi: 10.2466/pms.107.3.691-706.

  PMID: 19235401 BACKGROUND

MeSH Terms

Conditions

Parasomnias; Depression; Anxiety Disorders

Condition Hierarchy (Ancestors)

Sleep Wake Disorders; Nervous System Diseases; Mental Disorders; Behavioral Symptoms; Behavior

Study Officials

• Birna Baldursdottir, PhD

  Reykjavík University, Iceland

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor

Study Record Dates

• First Submitted: May 29, 2026
• First Posted: June 22, 2026
• Study Start: March 6, 2019
• Primary Completion: April 8, 2019
• Study Completion: April 8, 2019
• Last Updated: June 25, 2026

Record last verified: 2026-06

Data Sharing

• IPD Sharing: Will share

Locations

IC (1)