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The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been endorsed by the ANZCTR. Before participating in a study, talk to your health care provider and refer to this information for consumers
Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Retrospectively registered

Titles & IDs
Public title
Acute alerting effects of daytime exposure to specific wavelengths of light
Scientific title
The effectiveness of exposure to different colours of light in improving alertness and psychomotor vigilance in sleep restricted and non-sleep restricted healthy adult participants
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Primary health condition: Alertness and psychomotor vigilance in healthy human volunteers. 2132 0
Condition category
Condition code
Mental Health 2228 2228 0 0
Studies of normal psychology, cognitive function and behaviour

Study type
Description of intervention(s) / exposure
Intervention: Ocular exposure to specific monochromatic wavelengths of light administered using a specialised light delivery system.
For three hours, each participant will be exposed to one of the following wavelengths of light: violet light (420nm), blue light (460nm), green light (555nm), or red light (620nm).
Intervention code [1] 1632 0
Intervention code [2] 2651 0
Treatment: Devices
Comparator / control treatment
No treatment (i.e. no exposure to light other than background room lighting)
Control group

Primary outcome [1] 3942 0
Psychomotor Vigilance Task mean reaction time (msec).
Timepoint [1] 3942 0
During and immediately after light exposure, expressed relative to baseline (i.e. immediately before light exposure).
Secondary outcome [1] 6623 0
Subjective sleepiness rating on the Karolinska Sleepiness Scale.
Timepoint [1] 6623 0
During and immediately after light exposure, expressed relative to baseline (i.e. immediately before light exposure).

Key inclusion criteria
(1) Male and female adults aged 18 to 30 years inclusive
(2) Healthy
Minimum age
18 Years
Maximum age
30 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
(1) Individuals who have engaged in shiftwork/nightwork in the past 3 years and/or transmeridian travel in the past 3 months.
(2) Individuals who smoke, report high caffeine intake and/or high alcohol consumption.
(3) Individuals who screen positive for drugs of abuse following comprehensive urine toxicological analysis.
(4) Women who are pregnant, lactating or planning to become pregnant during the study period.
(5) A history of alcohol/drug dependence.
(6) Current, recent (<3 months) or chronic history of use of drugs or medication that affect the central nervous system (except non-steroid topical creams, oral contraceptives and occasional use of mild pain killers.
(7) History of psychiatric illness.
(8) Recent acute or chronic medical illness.
(9) Abnormal sleep patterns/sleep disorders.
(10) Auditory defects.
(11) Any form of photophobia including drug-induced, epilepsy, seizures, vertigo or migraine.
(12) Individuals with diseases of the visual system.
(13) Females who are not taking a medically approved form of birth control.

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Allocation involves contacting the holder of the allocation schedule who is off-site.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation by using a randomisation table from a statistic book
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?

Intervention assignment
Other design features
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)
Recruitment postcode(s) [1] 605 0

Funding & Sponsors
Funding source category [1] 3176 0
Government body
Name [1] 3176 0
National Health and Medical Research Council
Address [1] 3176 0
Level 5
20 Allara Street
Canberra ACT 2601
Country [1] 3176 0
Primary sponsor type
Monash University
Wellington Rd
Clayton Victoria 3800
Secondary sponsor category [1] 2162 0
Name [1] 2162 0
Address [1] 2162 0
Country [1] 2162 0

Ethics approval
Ethics application status
Ethics committee name [1] 5155 0
Alfred Hospital Human Ethics Committee
Ethics committee address [1] 5155 0
Ethics committee country [1] 5155 0
Date submitted for ethics approval [1] 5155 0
Approval date [1] 5155 0
Ethics approval number [1] 5155 0
Ethics committee name [2] 5158 0
Monash University Standing Committee on Ethics in Research involving Humans (SCERH)
Ethics committee address [2] 5158 0
Ethics committee country [2] 5158 0
Date submitted for ethics approval [2] 5158 0
Approval date [2] 5158 0
Ethics approval number [2] 5158 0

Brief summary
This study examines the effects of different colours of light on sleepiness and performance on various tasks. It is predicted that exposure to blue light will reduce sleepiness and improve performance more effectively than other colours of light.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 27566 0
Address 27566 0
Country 27566 0
Phone 27566 0
Fax 27566 0
Email 27566 0
Contact person for public queries
Name 10821 0
Dr. Shantha.Rajaratnam
Address 10821 0
Monash University
School of Psychology, Psychiatry and Psychological Medicine
Building 17 (PO Box 17)
Clayton Victoria 3800
Country 10821 0
Phone 10821 0
+61 3 99053934
Fax 10821 0
Email 10821 0
Contact person for scientific queries
Name 1749 0
Dr. Shantha.Rajaratnam
Address 1749 0
Monash University
School of Psychology, Psychiatry and Psychological Medicine
Building 17 (PO Box 17)
Clayton Victoria 3800
Country 1749 0
Phone 1749 0
+61 3 99053934
Fax 1749 0
Email 1749 0

No information has been provided regarding IPD availability
Summary results
No Results