A retrospective cohort study from Japan found patients who experienced understaffing in hospital settings faced significantly worse, and sometimes fatal, outcomes.
The study reported that patients exposed to understaffing over a 24-hour period – particularly during day shifts – faced a higher risk of in-hospital mortality and readmission rates to those who experienced adequate care during their visits.
Co-author Niroko Morioka explained that “[t]he underlying mechanism is that low nurse staffing levels have been associated with missed nursing care, which in turn may lead to adverse patient outcomes…as well as inadequate discharge preparation resulting in higher rates of readmission.”
These findings aligned with previous research from other countries including England and the US, underscoring the widespread issue of hospital nurse understaffing and its harmful impact on patient outcomes. Earlier this year, nurses in New York City took industrial action over 41 days, resulting in increased wages, commitment to safe staffing levels, and protections against AI.
Interestingly, the study found that understaffing during evening and night shifts were not linked to these same negative outcomes. However, understaffing across all three time periods – including daytime – was linked to increased length of stay.
Concerns about the impact of inadequate staffing are not new. A similar 2008 study from Japan also found that nurses working under sufficient staffing levels were more likely to experience burnout, dissatisfaction, and to report “poor or fair quality of care” compared to their better staffed cohort.
In an accompanying commentary, University of Pennsylvania PdH candidates and RNs Karen Lasater and Linda Aiken noted that “it is discouraging, although typical, that more than 15 years passed between the two studies in Japan on the same topic without serious policy attention to persistent hospital nurse understaffing associated with potentially preventable deaths…”.
Lasater and Aiken urged Japan to look at examples of safe staffing standards in parts of Australia and Canada. Morioka similarly emphasised that “[o]ngoing monitoring of daily nurse staffing and addressing understaffing relative to the current annual median or higher may contribute to improved patient outcomes,” and joined her co‑authors in calling for immediate action from hospital leaders and policymakers.
