Original publication: 2021 | NIHR Public Health Research full report
Source authors: Sarah Cockayne and colleagues
Research programme: SSHeW — this is one of three documents from the same trial programme.
About this research
Can choosing footwear with genuinely better slip resistance reduce accidents at work?
Footwear manufacturers may describe their products as slip-resistant or compliant with relevant standards, but the practical question for employers is whether the shoes they provide actually reduce the risk of slipping. The SSHeW study — Stopping Slips among Healthcare Workers — set out to answer that question through a large, real-world randomised controlled trial.
Led by the University of York with HSE and NHS collaborators, the research assessed whether offering high-performing footwear could reduce workplace slips among NHS staff.
How the research was conducted
A total of 4,553 NHS employees were randomly allocated to two groups. 2,275 were offered footwear that had achieved a five-star HSE GRIP rating, while 2,278 continued using their usual work footwear. Participants reported their workplace slips during 14 weeks of follow-up.
The principal outcome was the rate of self-reported slips, with further examination of falls caused by slips and other related outcomes.
The study was particularly valuable because it moved beyond comparing laboratory friction values: it examined whether an intervention based on footwear performance translated into fewer actual slipping events.
Key findings
Workplace slips were substantially less frequent among staff offered high-performing footwear.
The intervention group reported 2,633 slips, compared with 4,110 slips among the control group. After adjustment, the incidence rate ratio was 0.63 (95% confidence interval 0.57–0.70), representing a 37% lower rate of slips.
Falls resulting from slips were also less frequent.
The adjusted incidence rate ratio for falls caused by slipping was 0.51 (95% confidence interval 0.28–0.92): approximately 49% lower, although with greater statistical uncertainty than the primary slip outcome.
Selecting footwear based on measured grip can make a practical difference.
The study provides evidence that choosing footwear with demonstrated slip resistance, rather than relying only on general marketing descriptions or nominal compliance, can reduce workplace slipping.
Interpreting the findings
The trial was randomised and large, providing stronger evidence for a real-world preventive effect than a simple laboratory ranking or observational comparison. Nevertheless, slip events were self-reported, staff could not be blinded to the footwear they received, and the intervention was the offer and provision of footwear rather than a controlled measurement of every step taken by every participant.
The results apply directly to the particular footwear intervention and NHS working conditions studied. They should not be interpreted as proof that any shoe marketed as slip-resistant would deliver the same benefit.
The associated programme included supplementary measurements of footwear using the earlier Shoe Slip Tester, including assessments of control footwear and worn intervention shoes. Those measurements were not the basis for choosing the trial's intervention shoes; they were selected using HSE GRIP ratings. The trial should therefore not be described as validating a later commercial testing machine.
Why it matters
For employers and PPE buyers, SSHeW provides a clear reason to look beyond basic certification when selecting footwear. Different products can provide different levels of traction, and selecting footwear on the basis of meaningful performance evidence can reduce incidents.
The study also demonstrates why the most persuasive slip-resistance research connects physical testing with outcomes experienced by real workers.
Original research
Cockayne and colleagues (2021). Slip-resistant footwear reduces slips among National Health Service workers in England: a randomised controlled trial. Occupational and Environmental Medicine, 78, 472–478. DOI: 10.1136/oemed-2020-106914.
Cockayne and colleagues (2021). Slip-resistant footwear to reduce slips among health-care workers: the SSHeW RCT. NIHR Public Health Research, 9(3). DOI: 10.3310/phr09030.
Original source and further reading
Publisher / original publication