Association between light sensitivity and circadian rhythm in children

Association between light sensitivity and circadian rhythm in children - Association between light sensitivity and circadian rhythm in children

Status

Active, not recruiting

Phases

Unknown

Study type

Interventional

Source

JPRN

Registry ID

JPRN-UMIN000031391

Enrollment

Registered

2018-02-21

Start date

2016-09-01

Completion date

Unknown

Last updated

2026-06-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Healthy volunteer

Interventions

Adult group I First night: Dim lighting (&lt

30 lx) Second night: LED lighting (color temperature: 3000 K, illumination: approximately 270 lx) Adult group II First night: Dim lighting (&lt

30 lx) Second night: LED lighting (color temperature: 6200 K, illumination: 270 lx) Child group I First night: Dim lighting (&lt

30 lx) Second night: LED lighting (color temperature: 3000 K, illumination: approximately 270 lx) Child group II First night: Dim lighting (&lt

30 lx) Second night: LED lighting (color temperature: 6200 K, illumination: 270 lx)

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: Healthy Male or female children (elementry school students) and their parents

Exclusion criteria

Exclusion criteria: 1)Subjects who take hyponotics and sedatives 2)Subjects who are shift worker or night worker

Design outcomes

Primary

Measure	Time frame
Salivary melatonin concentration	—

Secondary

Measure	Time frame
Karolinska. Sleepiness Scale (KSS) Psychomotor Vigilance Task (PVT)	—

Countries

Japan

Contacts

Public ContactSang-il Lee

Hokkaido University Division of Human Environmental Systems

si.lee@eng.hokudai.ac.jp011-706-6282

Outcome results

None listed

Source: JPRN (via WHO ICTRP) · Data processed: Jul 3, 2026