A cross-sectional survey published in BMJ Open on Thursday found that 71% of responding NHS shift workers met the criteria for probable shift work disorder, Science Media Centre reported. The study, led by Thavapriya Sugavanam and colleagues, drew on 500 respondents from two NHS trusts who volunteered for a survey that specifically emphasised sleep problems.
Two outside experts urged caution about reading the 71% figure as applying to the whole NHS workforce. Dr Nina Rzechorzek, an MRC Clinician Scientist in brain temperature and neural circadian rhythms at the University of Cambridge, said the volunteer sample meant the figure “cannot be generalised to the wider NHS workforce.” Dr Gavin Stewart, a Campbell Collaboration methods editor and senior lecturer in evidence synthesis at Newcastle University, noted that the sample size of only 500 respondents and the restriction to two trusts meant the conclusions “are best considered as preliminary.”
Experts warn against medicalising a scheduling mismatch
Rzechorzek said the researchers did not assess chronotype — an individual’s biologically influenced tendency toward earlier or later sleep-wake timing — which has a substantial genetic component and may significantly affect tolerance of different shift patterns. “Shift work disorder is a recognised condition, but we should be careful not to medicalise what may fundamentally be a mismatch between biological timing and occupational schedules,” she said. Improving shift scheduling and developing methods to match workers to suitable schedules based on their biological timing, she added, “deserves at least as much attention as identifying and treating affected individuals.”
The study, titled “Prevalence and associated burden of shift work disorder (SWD) in healthcare shift workers in the UK National Health Service (NHS): a cross-sectional survey,” was published at 23:30 UK time on 5 November 2026.
Wider research points to depression risk and organizational fixes
A study of new paramedics published via ScienceDirect found that after 12 months of rotating shift work, 18.5% were at high risk for shift work disorder, and that depression symptoms measured before starting shift work — but not anxiety — predicted that risk a year later. A literature review hosted on PubMed Central, searching publications from June 2012 onward, identified organizational determinants that should be prioritised in risk assessment, including the number of nights worked per year, long night-time working hours, frequent missed nap opportunities during night shifts, quick returns between shifts, and unhealthy workplaces. The review concluded that organizational interventions targeting healthy shift-work scheduling and workplace safety are proposed to moderate the occurrence of shift work disorder.
What the 71% figure does and does not tell us
The survey’s authors and the reacting experts agree on the practical stakes: shift work disorder in healthcare workers is linked to poor sleep, sleepiness, and — per the PubMed Central review — potentially higher service costs and lower standards of care. What remains open is how common the condition is across the entire NHS, because the survey sample volunteered for a sleep-focused questionnaire and covered only two trusts.
Shift work disorder in the NHS: your questions answered
Does the 71% figure apply to every NHS worker? No. Science Media Centre reported that Rzechorzek cautioned the figure cannot be generalised because participants volunteered for a survey that specifically emphasised sleep problems, and Stewart noted the 500 respondents came from only two trusts.
What role does chronotype play? The BMJ Open study did not measure it, but Rzechorzek said chronotype has a substantial genetic component and may significantly affect how well someone tolerates or adapts to different shift patterns.
Are paramedics affected too? Yes. A ScienceDirect study of new paramedics found 18.5% were at high risk for shift work disorder after 12 months of rotating shifts, with pre-existing depression symptoms predicting that risk.
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