Nurse understaffing increases their chances of going off sick

A study by the University of Southampton has found not having enough registered nurses on a ward leads to higher rates of illness among this nursing staff group.

The research shows that the higher the proportion of registered nurses on a ward, compared to nursing support staff, the less incidents there are of registered nurse sickness.

The findings, published in the journal JAMA Network, also reveal that nurses working long shifts over a period of several days are more prone to being off sick than those on shorter ones.

The researchers examined data from four acute care hospitals in England over a four year period (April 2015 – February 2020) – covering over 18,000 registered nurses and nursing support staff. They looked at factors such as nursing team skill-mix, understaffing and shift length. For some two-and-a-half million shifts worked, there were just over 43,000 sickness episodes.

The team found that when moving from a staffing mix where just over half are registered nurses, to a mix of three quarters, there is a four percent reduction in the chances of registered nurses being off unwell. For every 10 percent increase in the proportion of registered nurses working on a ward, there is a two percent reduction in incidents of sickness.

The study also showed that when full-time registered nurses experienced more understaffing during a working week, sickness absence increased in the following week. Understaffing in nursing support staff didn’t contribute to sickness rates across either staff groups.

In addition, the research revealed a 26 percent increase in the odds of a registered nurse reporting in sick when their shifts are all long ones (12+ hours) in the preceding seven days, when compared to nurses working no long shifts at all.

Lead investigator Dr Chiara Dall’ora comments: “Our findings are significant because the nursing workforce is under increasing pressure, with not enough nurses entering the profession, and many leaving their jobs due to stress-related sickness and burnout. We hope our work can help inform those in charge of planning workforce strategy and scheduling.”

Co-author Professor Peter Griffiths adds: “Increasing registered nurse staffing levels has been associated with improved outcomes for patients and could be a cost-effective strategy for improving the quality and safety of care. Our study adds to this body of evidence by shining a light on the additional impact on nurses’ health and wellbeing.”

The researchers conclude that although increasing the registered nurse skill mix and reducing their understaffing may lead to what appear, at first glance, to be modest gains, the effects of even small improvements in working conditions could actually go a long way to improving productivity, and may reduce staff turnover, at what is a crucial time for the health service.

Ends
 

Notes to Editors

1. The paper ‘Nurse staffing configurations and nurse absence due to sickness: longitudinal study’ is published in the journal JAMA Network DOI: http://jamanetwork.com/journals/jamanetworkopen/fullarticle/10.1001/jamanetworkopen.2025.5946?utm_source=For_The_Media&utm_medium=referral&utm_campaign=ftm_links&utm_term=042225
    
2. For interviews contact Peter Franklin, Media Relations, University of Southampton – press@soton.ac.uk 023 8059 3212.
    
3. For more about Health Sciences at the University of Southampton visit: https://www.southampton.ac.uk/about/faculties-schools-departments/school-of-health-sciences
    
4. The University of Southampton drives original thinking, turns knowledge into action and impact, and creates solutions to the world’s challenges. We are among the top 100 institutions globally (QS World University Rankings 2025). Our academics are leaders in their fields, forging links with high-profile international businesses and organisations, and inspiring a 22,000-strong community of exceptional students, from over 135 countries worldwide. Through our high-quality education, the University helps students on a journey of discovery to realise their potential and join our global network of over 200,000 alumni. www.southampton.ac.uk