The effect of Quick Returns on Sleep and Performance

Employees are entitled to at least 11 consecutive hours off between two work shifts ^{1, 2}. If shorter, it is referred to as a «quick return» ³. By agreement between the employer and safety representatives, time off between shifts can be reduced to 8 hours ². Based on international studies, we know that quick returns often last between 8 – 9 h and that they most frequently occur between an evening- and a day shift ³.

One consequence of quick returns, is curtailed sleep ^{3, 4, 5}. Previous studies have however only measured sleep using sleep diaries/actigraphy. Thus, we do not know how for instance the sleep stages are affected during a quick return. Quick returns have also been associated with work related accidents ^{6, 7, 8}. These studies are however based on reports following the incidents, meaning that actual performance during quick returns have currently not been measured.

The aim of the project is to provide greater knowledge regarding how sleep and performance are affected during a quick return. This will be done by simulating quick returns in a laboratory. Participants will be present in the laboratory for two conditons: 

1.  «Day-day condition». Participants are present in the laboratory for two consecutive day shifts (07:00 – 15:00). This yields 16 hs time off between the shifts.  
2. «Quick return condition». Participants are present in the laboratory for an evening shift (15:00 – 23:00), followed by a day shift. This yields 8 hs time off between the shifts.  

A few days before and between the simulated shifts, the participants' sleep is measured through sleep diaries and a sleep radar when they sleep at home. During the simulated shifts, the participants perform repeated and different performance tests. This indicates how performance changes over time and how different areas of performance are affected.

More information about the study

• Information about the project at Clinical Trials.
• Information about the project at Regional Committee for Medical and Health Research Ethics can be found by searching for case number ("saksnummer") «234184» in the project library in the REK-portal. 

References

1. https://www.arbeidstilsynet.no/regelverk/lover/arbeidsmiljoloven/10/10-8/
2. https://eur-lex.europa.eu/EN/legal-content/summary/organisation-of-worki...
3. Vedaa, Ø., Harris, A., Bjorvatn, B., Waage, S., Sivertsen, B., Tucker, P., & Pallesen, S. (2016). Systematic review of the relationship between quick returns in rotating shift work and health-related outcomes. Ergonomics, 59(1), 1-14.
4. Vedaa, Ø., Mørland, E., Larsen, M., Harris, A., Erevik, E., Sivertsen, B., ... & Pallesen, S. (2017). Sleep detriments associated with quick returns in rotating shift work. Journal of occupational and environmental medicine, 59(6), 522-527.
5. Ganesan, S., Magee, M., Stone, J. E., Mulhall, M. D., Collins, A., Howard, M. E., ... & Sletten, T. L. (2019). The impact of shift work on sleep, alertness and performance in healthcare workers. Scientific reports, 9(1), 4635.
6. Vedaa, Ø., Harris, A., Erevik, E. K., Waage, S., Bjorvatn, B., Sivertsen, B., ... & Pallesen, S. (2019). Short rest between shifts (quick returns) and night work is associated with work-related accidents. International archives of occupational and environmental health, 92, 829-835.
7. Vedaa, Ø., Harris, A., Waage, S., Bjorvatn, B., Thun, E., Buchvold, H. V., ... & Pallesen, S. (2020). A longitudinal study on the association between quick returns and occupational accidents. Scandinavian Journal of Work, Environment & Health, 46(6), 645.
8. Nielsen, H. B., Hansen, Å. M., Conway, S. H., Dyreborg, J., Hansen, J., Kolstad, H. A., ... & Garde, A. H. (2019). Short time between shifts and risk of injury among Danish hospital workers. Scandinavian journal of work, environment & health, 45(2), 166-173.
9. https://clinicaltrials.gov/study/NCT05162105?cond=Quick%20returns&rank=1