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Trial registered on ANZCTR


Registration number
ACTRN12621000686808
Ethics application status
Approved
Date submitted
1/12/2020
Date registered
4/06/2021
Date last updated
4/06/2021
Date data sharing statement initially provided
4/06/2021
Type of registration
Retrospectively registered

Titles & IDs
Public title
The Impact of Watch Keeping Schedules on Cognitive Performance and Physiology in Adults
Scientific title
The Impact of Watch Keeping Schedules on Cognitive Performance and Physiology in Adults
Secondary ID [1] 302018 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Cognitive performance and physiological changes in healthy adults experiencing circadian misalignment 318587 0
Condition category
Condition code
Neurological 316610 316610 0 0
Studies of the normal brain and nervous system
Mental Health 319890 319890 0 0
Studies of normal psychology, cognitive function and behaviour

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Trained research assistants will deliver ten x 9 night lab study runs, monitoring participant adherence to the protocol at all times during the 10 day in-laboratory visit which will be overseen by the chief investigators of the study. will be conducted, with 16 participants undergoing a two-watch routine (2 conditions, 12h on and 12 off watch) 12) and 16 participants undergoing a three section watch routine (2 conditions, 8h on 16h off watch). On training day (day 1) participants will be talked through each neurobehavioral task and be given time to ask questions and familiarise themselves with the laboratory, followed by an 8h acclamation sleep. Participants will be given 6.5 hour sleep opportunities in each condition. The conditions differ in the timing of this sleep opportunity; A) 0930 to 1600, B) 0830 to 1230 and 2130 to 0000 C) 1800 to 0030, D) 0130 to 0800. On the 9th night participants will be given a 8h recovery sleep from 2300 to 0700. Neurobehavioural and physiological functioning will be measured in blocks simulating shifts; A) 0000 to 0900 and 1700 to 2100, B) 0000 to 0700 and 1300 to 1900, C) 0000 to 0500 and 1300 to 1700. D) 0900 to 1300 and 2100 to 0100. Variables that will be measured from the laboratory will be: a) Cognitive performance: Psychomotor Vigilance task (reaction time and errors), cognitive throughput (number correct), working memory (correct answers), vigilant attention (maintenance of performance), decision making (correct responses), inhibition (correct responses), CRUSE Submarine simulator (situation awareness) b) Team work task (COHESION task) c) Physiological state: heart rate, heart rate variability d) Eye tracking (desk mounted eye tracking device used during simulated drive) e) Salivary and blood cortisol and melatonin f) Sleep monitoring: sleep onset latency, sleep quality, percent time in each sleep stage, total sleep time, arousals g) Subjective ratings of fatigue, sleepiness, performance, and questionnaires on mood, physiological symptoms. Saliva samples will be taken at 2h intervals on each day of the protocol. Blood samples will be taken once at baseline and once following recovery sleep.
All sleeps will be recorded by standard polysomnography. As part of this recording, electrodes will be attached to participants' scalps, the skin on their face, chin and chest during the scheduled sleep, to measure their brain activity and heart rate during sleep.
All sleeps will be recorded by standard polysomnography. As part of this recording, electrodes will be attached to participants' scalps, the skin on their face, chin and chest during the scheduled sleep, to measure their brain activity and heart rate during sleep.
Intervention code [1] 318312 0
Behaviour
Comparator / control treatment
Condition D with night time sleep during the night will act as the comparator
Control group
Active

Outcomes
Primary outcome [1] 324724 0
Brain activity (sleep) measured using polysomnography (electrodes will be attached to participants' scalp, and the skin on their face, chin and chest)
Timepoint [1] 324724 0
Continuously during scheduled sleep periods and simulated drive
Primary outcome [2] 324726 0
Melatonin (circadian marker) measured by a saliva sample
Timepoint [2] 324726 0
Measured approximately 2-hourly throughout wake periods.
Primary outcome [3] 324727 0
Cognitive performance as measured by Psychomotor Vigilance task
Timepoint [3] 324727 0
Measured at approximately 2-hourly intervals during wake periods
Secondary outcome [1] 385588 0
Cognitive performance as measured by AusEd driving simulator task
Timepoint [1] 385588 0
Measured approximately once every 4h during the simulating shifts; A) 0000 to 0900 and 1700 to 2100, B) 0000 to 0700 and 1300 to 1900, C) 0000 to 0500 and 1300 to 1700. D) 0900 to 1300 and 2100 to 0000.
Secondary outcome [2] 394515 0
Heart rate variability measured using electrocardiography
Timepoint [2] 394515 0
Continuously during scheduled sleep periods and simulated drive
Secondary outcome [3] 394516 0
Subjective measure of cognitive performance measured by Visual Analogue Scale
Timepoint [3] 394516 0
Approximately 2-hourly during wake periods of the experimental phase of the study
Secondary outcome [4] 394517 0
Cortisol (stress marker) levels as measured by a saliva sample
Timepoint [4] 394517 0
Measured approximately 2-hourly throughout wake periods
Secondary outcome [5] 394896 0
Cognitive performance as measured by Cohesion test (15 min problem solving test)
Timepoint [5] 394896 0
Measured approximately once every 4h during the simulating shifts; A) 0000 to 0900 and 1700 to 2100, B) 0000 to 0700 and 1300 to 1900, C) 0000 to 0500 and 1300 to 1700. D) 0900 to 1300 and 2100 to 0000.
Secondary outcome [6] 394897 0
Cognitive performance as measured by Sternberg working a 20 min memory task
Timepoint [6] 394897 0
Measured approximately once every 4h during the simulating shifts; A) 0000 to 0900 and 1700 to 2100, B) 0000 to 0700 and 1300 to 1900, C) 0000 to 0500 and 1300 to 1700. D) 0900 to 1300 and 2100 to 0000.
Secondary outcome [7] 394898 0
Cognitive performance as measured by Automated Neuropsychological Assessment Metrics (ANAM) (30 min battery of short (1-3 min) cognitive tests
Timepoint [7] 394898 0
Measured approximately once every 4h during the simulating shifts; A) 0000 to 0900 and 1700 to 2100, B) 0000 to 0700 and 1300 to 1900, C) 0000 to 0500 and 1300 to 1700. D) 0900 to 1300 and 2100 to 0000.
Secondary outcome [8] 394899 0
Cognitive performance as measured by CRUSE Submarine simulator (a 30min computer based console simulation.
Timepoint [8] 394899 0
Measured approximately once every 4h during the simulating shifts; A) 0000 to 0900 and 1700 to 2100, B) 0000 to 0700 and 1300 to 1900, C) 0000 to 0500 and 1300 to 1700. D) 0900 to 1300 and 2100 to 0000.
Secondary outcome [9] 394900 0
Subjective measures of sleepiness measured by the Karolinska Sleepiness Scale (KSS)
Timepoint [9] 394900 0
Measured at approximately 2-hourly intervals during wake periods

Eligibility
Key inclusion criteria
Healthy, young adults (18-40 years) with normal sleep/wake behaviour (self reported).
Minimum age
18 Years
Maximum age
40 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Self reported habitual nightly sleep amounts < 6 or > 9 hours; self reported night time lights out earlier than 2100 hours during weeknights; self reported morning wake-up times
later than 0900 during weekdays; self reported habitual napping > 1 time a week; self reported caffeine use > 400 mg (e.g. 8 caffeinated sodas or approximately 3 to 4 cups of coffee) per day, history of cardiovascular disease (including but not limited to arrhythmias, valvular heart disease, congestive heart failure, or myocardial infarction); history of neurologic disorder (including but not limited to epilepsy or another seizure disorder,
amnesia for any reason, hydrocephalus, MS, narcolepsy or other sleep disorder); underlying pulmonary disease requiring daily inhaler use; kidney disease or abnormalities, liver disease or abnormalities; self reported history of psychiatric disorder requiring hospitalization or psychiatric product for any length of time; self reported or suspected regular nicotine use (> 1 cigarette or equivalent per week) within the last year; self reported or suspected heavy alcohol use (minimum limit to define heavy alcohol use is 14 drinks per week or as determined by the examining study licensed physician); self reported or suspected current use of other illicit drugs (including but not limited to benzodiazepines, amphetamines, cocaine, marijuana); resting blood pressure above 140/90 or resting pulse > 110; BMI > 30 (Obese Class I or greater); clinically significant values (as determined by the reviewing study physician) for any haematology or chemistry parameter; positive urine drug result during screening visit; currently taking corticosteroid or anti-inflammatory medications.

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Central randomisation by computer using the online research randomizer tool (https://www.randomizer.org/)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation using a randomisation table created by computer software (i.e. computerised sequence generation) at run level
Masking / blinding
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Mixed Model Analysis of Variance (ANOVA) will be employed, including a random factor for subjects and fixed repeated measures effects for watch routine group and test session. A fixed between subjects (grouping) factor also will be included. Other analytical procedures
(e.g. regression and/or discontinuous growth modeling) may be used to evaluate circadian markers between the different sample types collected.

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
Actual
15/01/2021
Date of last participant enrolment
Anticipated
31/03/2022
Actual
Date of last data collection
Anticipated
7/04/2022
Actual
Sample size
Target
40
Accrual to date
4
Final
Recruitment in Australia
Recruitment state(s)
SA

Funding & Sponsors
Funding source category [1] 306438 0
Government body
Name [1] 306438 0
Defence Science and Technology Group - Australian Government Department of Defence
Country [1] 306438 0
Australia
Primary sponsor type
Government body
Name
Defence Science and Technology Group - Australian Government Department of Defence
Address
DST Headquarters
F2-2-03
PO Box 7931
Canberra BC ACT 2610
Country
Australia
Secondary sponsor category [1] 306955 0
None
Name [1] 306955 0
Address [1] 306955 0
Country [1] 306955 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 306647 0
University of South Australia Human Research Ethics Committee
Ethics committee address [1] 306647 0
University of South Australia
Magill Campus
St Bernards Rd
Magill, SA, 5072
Ethics committee country [1] 306647 0
Australia
Date submitted for ethics approval [1] 306647 0
Approval date [1] 306647 0
03/08/2020
Ethics approval number [1] 306647 0

Summary
Brief summary
Modern navies are focused on trying to shrink the size of their crews to exploit the benefits of new achievements in automation of ships systems. While technological advances are enablers, the performance of these advanced systems is only as good as the crews who man them. The ability to remain vigilant for an automation failure is impacted more severely by fatigue than are other mental functions. From a fatigue management point of view, most navies have sub-optimal watch systems that unnecessarily fatigue naval crews which results in sub-optimal crew performance.

An overlooked opportunity exists on Subsurface vessels in that the natural light dark cycles can be manipulated. Theoretically this would be advantageous for a 2 watch system, but this is never been attempted under laboratory conditions.

We hypothesise that sleep, cognitive performance, and physiological measures will differ between the watches within both a two-watch routine, and a three-watch routine.

The research question is whether a two-watch or three-watch routine lead to better sleep, cognitive performance, and physiological functioning.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 104542 0
Prof Siobhan Banks
Address 104542 0
University of South Australia
Magill Campus
Sleep and Chronobiology Laboratory
St Bernards Rd
Magill, SA, 5072
Country 104542 0
Australia
Phone 104542 0
+618 8302 1712
Fax 104542 0
Email 104542 0
[email protected]
Contact person for public queries
Name 104543 0
Siobhan Banks
Address 104543 0
University of South Australia
Magill Campus
Sleep and Chronobiology Laboratory
St Bernards Rd
Magill, SA, 5072
Country 104543 0
Australia
Phone 104543 0
+618 8302 1712
Fax 104543 0
Email 104543 0
[email protected]
Contact person for scientific queries
Name 104544 0
Siobhan Banks
Address 104544 0
University of South Australia
Magill Campus
Sleep and Chronobiology Laboratory
St Bernards Rd
Magill, SA, 5072
Country 104544 0
Australia
Phone 104544 0
+618 8302 1712
Fax 104544 0
Email 104544 0
[email protected]

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
Approval has not been granted to share individual participant data.


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.