Effects of Morningness on Night Split Shift Performance

NCT06440434 | Active Not Recruiting

• 1 other identifier: M3447
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

The goal is to investigate if the morningness-eveningness dimension mediates sleep and function on spilt night shifts (midnight-4am and 4am-8am). Does those with high score of morningness function relatively better on the last compared to the first split shift? Participants will: Record their sleep from 2 days prior to 2 days following the split shift During the shifts complete questionnaires assessing mood, sleepiness and perceived performance as well as complete cognitive tests: Psychomotor vigilance test, digit symbol substitution test, working memory scanning test, reversal learning test, and visual search test

Conditions

Shift-work Disorder

Outcome Measures

Primary Outcomes (3)

• Total sleep time

  Total sleep (sleep diary and radar). Higher values indicates more sleep

  Total sleep time between 6pm day before shift start to 6pm the day the shift end for both early night shift (midnight-04am) and late night shift (04am-08am)

• Psychomotor Vigilance Test (PVT)

  Reaction time (mean 1/RT) and number of lapses (RTs≥500 ms). For mean 1/RT higher values are associated with best performance, on lapses higher values are associated with worst performance

  Hourly during shifts (0:15am, 1:15am, 2:15am and 3:15am on early night shift; 4:15am, 5:15am, 6:15am and 7:15 am on late night shift)

• Karolinska Sleepiness Scale (KSS)

  Assessment of state sleepiness, range 1-9 (higher scores indicate worse state)

  Hourly during shifts (0:15am, 1:15am, 2:15am and 3:15am on early night shift; 4:15am, 5:15am, 6:15am and 7:15 am on late night shift)

Secondary Outcomes (7)

• Sleep efficiency (percentage of time in bed one sleeps)

  Between 6pm day before shift start to 6pm the day the shift end for both early night shift (midnight-04am) and late night shift (04am-08am)

• Positive and Negative Affect Schedule (PANAS)

  Hourly during shifts (0:15am, 1:15am, 2:15am and 3:15am on early night shift; 4:15am, 5:15am, 6:15am and 7:15 am on late night shift)

• Self-rated performance

  Hourly during shifts (0:15am, 1:15am, 2:15am and 3:15am on early night shift; 4:15am, 5:15am, 6:15am and 7:15 am on late night shift)

• Digital Symbol Substitution Test

  Hourly during shifts (0:15am, 1:15am, 2:15am and 3:15am on early night shift; 4:15am, 5:15am, 6:15am and 7:15 am on late night shift)

• Working Memory Scanning Test (probed recall)

  Hourly during shifts (0:15am, 1:15am, 2:15am and 3:15am on early night shift; 4:15am, 5:15am, 6:15am and 7:15 am on late night shift)

Study Arms (2)

Early night shift (midnight-4am)

ACTIVE COMPARATOR

Behavioral: Time of night shift

Late night shift (4am - 8am)

ACTIVE COMPARATOR

Behavioral: Time of night shift

Interventions

Time of night shift BEHAVIORAL

Early vs. late night split night shift

Early night shift (midnight-4am); Late night shift (4am - 8am)

Eligibility Criteria

• Age: 18 Years - 40 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• years old
• no incorrectable vision problems

You may not qualify if:

• \* regular use of sleep medication

Sponsors & Collaborators

• University of Bergen: lead

Study Sites (1)

University of Bergen

Bergen, 5020, Norway

Location

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Masking Details: Randomly allocated to order of night shifts (midnight-4am vs.4am-8am)
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Model Details: A 2 (midnight-4am vs.4am-8am) within factor x 2 (below vs. above median on morningness) between factor experimental design

Study Record Dates

• First Submitted: May 14, 2024
• First Posted: June 3, 2024
• Study Start: April 19, 2024
• Primary Completion: June 20, 2024
• Study Completion: December 31, 2024
• Last Updated: June 13, 2024

Record last verified: 2024-06

Locations

NO (1)