Higher night-shift sleepiness was associated with lower self-reported cognitive control and cognitive flexibility, as well as lower self-reported shift handover effectiveness, with cognitive control and flexibility partially mediating the sleepiness-handover relationship.
Nurses' mean sleepiness score during night shifts was 6.41 out of 10, indicating moderate-to-high sleepiness overall.
Sleepiness progressively worsened across the night shift, with the highest levels recorded at 06:00 a.m.
Higher sleepiness was significantly associated with lower self-reported cognitive control and cognitive flexibility.
Higher sleepiness was significantly associated with lower self-reported shift handover effectiveness.
Cognitive control and cognitive flexibility partially mediated the relationship between sleepiness and self-reported shift handover effectiveness.
The structural equation model demonstrated acceptable goodness-of-fit for the proposed relationships.
The study was conducted using a cross-sectional descriptive design with a sample of 270 nurses and was reported in accordance with the STROBE checklist.
This research suggests that nurses working night shifts experience significant sleepiness that worsens as the shift progresses, starting at a moderate level around midnight and reaching high levels by 6:00 a.m. Among 270 nurses working in emergency, intensive care, and general hospital units in Türkiye, greater sleepiness was linked to nurses reporting poorer ability to control their thinking and adapt flexibly to changing situations — skills critical for safe patient care. More strikingly, sleepier nurses also reported less effective handovers, the structured communication process where care responsibility is transferred between shifts. The study also found that the impact of sleepiness on handover quality was not only direct but also worked indirectly by impairing cognitive functioning, which in turn further reduced handover effectiveness. In other words, sleepiness appears to undermine the mental sharpness nurses need to communicate critical patient information accurately during shift changes. These self-reported findings were supported by a statistical model that fit the data well. This research suggests that sleepiness in night-shift nurses is an important occupational health and patient safety concern. Because handovers are a well-recognized high-risk point for medical errors, anything that degrades handover quality — such as sleepiness — could have serious consequences for patients. The authors emphasize that healthcare organizations should consider monitoring nurse fatigue and exploring scheduling or fatigue-management strategies, while noting that longer-term studies across multiple sites are needed to determine which specific interventions are most effective.
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Upload Your LabsKaplan A, Özdemir C, Gökkaya Y. (2026). Sleepiness During Night Shifts and Nurses' Self-Reported Cognitive Control, Cognitive Flexibility, and Handover Effectiveness: A Cross-Sectional Study.. International nursing review. https://doi.org/10.1111/inr.70219