Forward vs Backward Shift Rotation: Which Is Better?
Forward rotation was linked to less sleepiness and better sustained attention, but poor sleep remained common in both groups.
Reviewed against primary sources on July 23, 2026 by the Soon operations research team. How we vet the evidence
The evidence in one line
A prospective cohort of 144 nurses at five Italian hospitals found backward-rotating schedules were associated with greater sleepiness and slower sustained-attention performance than forward rotation (Di Muzio et al., 2021). After the night shift, 93.8% of nurses on backward rotation reached elevated sleepiness, yet poor sleep quality was similarly common in both groups. Forward rotation is therefore a defensible design preference, not evidence that rotating work becomes harmless.
Rotation direction
Forward rotation performed better, but neither erased poor sleep
93.8%
Elevated sleepiness
Backward group after the night shift
57.5%
Poor sleep quality
Forward rotation group
57.8%
Poor sleep quality
Backward rotation group
The cohort included 144 nurses at five hospitals. Direction was associated with attention and sleepiness, but workers were not randomized to their schedules.
Direction changes the transition
Forward rotation moves from morning to afternoon to night, delaying the work period. Backward rotation moves against that direction and often compresses recovery between shift types. In the cohort, backward-rotating nurses showed greater sleepiness and slower reaction-time performance even after adjustment for age, employment duration, and sleep quality (Di Muzio et al., 2021).
The most memorable number is also narrow: 60 of 64 backward-rotating nurses, or 93.8%, reached a Karolinska Sleepiness Scale score of at least seven after the night shift. It describes one group at one measurement point, not the excess risk caused by backward rotation, and should not be compared with a percentage from another population as though it were an effect size.
Forward is preferable, not protective
Poor sleep quality affected 57.5% of the forward group and 57.8% of the backward group (Di Muzio et al., 2021). The direction changed sleepiness and vigilance measures, but it did not erase the broader sleep burden of rotating work. That is why expert consensus places forward rotation alongside limits on consecutive nights, shift duration, and rest rather than using it as a substitute for them (Garde et al., 2020).
The hospitals did not randomize nurses to rotation direction. Workplace, unit, or schedule differences could remain despite adjustment, and the sample was limited to 144 nurses. Use forward rotation as the default when rotation is necessary, then evaluate sleepiness, quick returns, and worker preference in the actual roster.
What this means for your schedule
- When rotating shifts are necessary, prefer morning to afternoon to night rather than the reverse sequence.
- Check whether the rotation creates short intervals between shift types, because direction and recovery time are partly intertwined.
- Keep the existing limits on consecutive nights, night-shift length, and rest; forward rotation does not replace them.
The business case
Rotation direction is often cost-neutral to change, making it a reasonable first design improvement when coverage remains constant.
Judge the change using sleepiness, quick-return frequency, absence, and worker preference rather than assuming direction alone solves fatigue.
Frequently asked questions
- What is a forward-rotating schedule?
- A forward rotation delays the work period, commonly moving from morning to afternoon to night. A backward rotation moves in the opposite direction. The exact labels can vary, so audit the sequence itself rather than relying on the name used in a scheduling system.
- How strong is the evidence for forward rotation?
- The featured study was a prospective observational cohort of 144 nurses at five hospitals, not a randomized trial (Di Muzio et al., 2021). Its objective attention tests strengthen the finding, but group and workplace differences may remain. The article therefore grades the evidence as emerging.
- Did forward rotation improve sleep quality?
- Not clearly in this cohort. Poor sleep quality was reported by 57.5% of forward-rotating nurses and 57.8% of backward-rotating nurses (Di Muzio et al., 2021). The meaningful differences appeared in sleepiness and sustained-attention measures, not the overall sleep-quality prevalence.
- Can forward rotation make night work safe?
- No. It is one design preference inside a broader fatigue-risk approach. Expert consensus also recommends no more than three consecutive nights, at least 11 hours between shifts, and night shifts no longer than nine hours (Garde et al., 2020).
Sources
Every figure on this page is drawn from a cited primary source and checked against the original publication.
Di Muzio, M., Diella, G., Di Simone, E., Pazzaglia, M., Alfonsi, V., Novelli, L., et al. (2021). Comparison of Sleep and Attention Metrics Among Nurses Working Shifts on a Forward- vs Backward-Rotating Schedule. JAMA Network Open, 4(10), e2129906. https://doi.org/10.1001/jamanetworkopen.2021.29906
Design: Prospective multicenter cohort study (144 nurses at 5 hospitals)
Garde, A. H., Harma, M., Bjorvatn, B., Bonde, J. P., Hansen, J., Hansen, A. M., et al. (2020). How to schedule night shift work in order to reduce health and safety risks. Scandinavian Journal of Work, Environment & Health, 46(6), 557โ569. https://pmc.ncbi.nlm.nih.gov/articles/PMC7737811/
Design: Expert-consensus paper (workshop of 15 shift-work researchers)
Cite these sources: BibTeX RIS
Why this page is graded emerging evidence
A single cohort, field, or simulator study. Worth knowing, not yet worth building policy on.
Who reviewed this
Every article in this library is checked against its primary sources by the Soon operations research team: each figure is traced back to the study it came from, and the wording is checked against the study design before publication. What that review covers
None of the studies cited here evaluated Soon.They examine scheduling practices, shift patterns, and working hours as studied by independent researchers, so their findings describe what those practices are associated with, not what any particular software produces.
This article summarizes published research for scheduling and operations decisions. It is not medical advice. Individual health questions belong with a qualified clinician.
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