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Updated: Jan 4, 2026

Collecting Sleep, Circadian, Fatigue, and Performance Data in Complex Operational Environments
Published on: August 8, 2019
What do people do before going to bed? A study of bedtime procrastination using time use surveys
Sun Ju Chung1, Hyeyoung An2, Sooyeon Suh2
1Department of Psychiatry, SMG-SNU Boramae Medical Center, Seoul, Republic of Korea.
Study Objectives:
Bedtime procrastination (BP) is defined as going to bed later than intended despite absence of external reasons. This study investigated sleep and psychological factors associated with BP in young adults, and further compared how high and low BP groups spend their time over 24 h and also 3 h prior to bedtime using time use surveys.
Methods:
Young adults (N = 106) from the community were classified as either high (n = 54) or low (n = 52) BP group based on the Bedtime Procrastination Scale. All participants were asked to complete questionnaires on insomnia, depression, anxiety, stress, and chronotype, in addition to keeping a 7-day sleep diary and completing time use surveys over 48 h.
Results:
Participants were 61.3% female, mean age 22.7 (±2.89) years old. Individuals in the high BP group reported significantly more depression, anxiety, and insomnia, went to bed later, woke up later, and had more eveningness tendencies compared to the low BP group. Results from the time use surveys revealed that the high BP group spent significantly more time engaging in leisure and social activity with the majority of time spent using media over 24 h compared to the low BP group. Finally, the high BP group spent on average approximately 451% (or 61 min) more time per day on their smartphone 3 h prior to bedtime compared to the low BP group.
Conclusions:
Our results suggest that BP is negatively associated with sleep and mood, and should be considered a serious health-interfering behavior.
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