Is “Winter pressure” on urgent and emergency care now seen all year?

It is commonly accepted that demand for NHS urgent and emergency care services increases during the Winter months, and there is a great deal of focus on how to manage this seasonal demand [1-4]. However, few studies exist directly comparing the characteristics of urgent and emergency care demand during the winter months with other times of year.  Additionally, some research suggests that the level of demand once only seen during Winter is now being experienced all year round [5-7].  Demand for emergency care has risen rapidly in recent years [8-9], with increasing numbers of attendances to emergency departments (EDs) and acute admissions being considered avoidable or ‘non-urgent’, in that suitable care could have been effectively delivered elsewhere and without the need for admission [10].  It is critical to understand the nature of demand on urgency and emergency care services to deliver effective care, but also to identify targets for intervention to reduce avoidable usage.

We recently headed an analysis funded by the NIHR and HDRUK to examine whether and how Winter pressures are currently manifesting in features of ED attendances and acute hospital admissions. This analysis took a novel ‘federated’ style of approach: we worked with several research institutions across the UK to rapidly access and analyse data from over 20 Type 1 EDs  and associated acute hospitals, facilitated by the Data Connect service [11].  Regional analysis teams produced summary descriptive and inferential statistics which were aggregated to produce a national picture of seasonal demand, and to understand regional variation.

We found very little difference in either the quantity or the nature of the demand for urgent and emergency care across the seasons. Figures 1 and 2 show that, while two sites showed greater numbers of ED attendances in Winter (defined here as October-March), there was no consistent picture of increased attendances or admissions during winter.  

Fig. 1.  Total acute admissions during the analysis period by site.

Fig. 2.  Total ED attendances during the analysis period by site.

Some of the key performance indicators we examined were the length of time waiting in ED, the chance of an ED attendance being non-urgent, the length of stay of a hospital admission, and the chance that the admission was avoidable.  We aggregated the results of adjusted regression analyses on these outcomes (fig. 3 & fig. 4), and found that although there was a lot of regional variation in ED waiting time, no measures showed a consistent effect of Winter, with some sites showing improved performance in Winter.  We also examined a number of demographics and clinical characteristics, but no features showed a notable or consistent difference by season.

Fig. 3.  Adjusted estimates of the effect of winter on ED waiting time (left) and the odds of an ED attendance being classified as non-urgent (right).

Fig. 4.  Adjusted estimates of the effect of winter on the odds of a hospital stay being 2 nights or more (left) and of an admission being classified as avoidable (right).

Given the consistent increase in demand for urgent care in recent years, it seems unlikely that previously seen seasonal pressure in Winter is reducing; rather it is likely that EDs and acute hospitals are seeing extremely high demand all year. Rather than focusing on managing demand during the Winter season, priorities should be focused on identifying means of reducing demand overall, optimising patient flow through the urgent care system, and increasing availability of and access to alternative urgent care options such as minor injury centres, out-of-hours GPs and same-day emergency care services.


Many thanks to the large number of researchers involved in curating and analysing the regional datasets that made this study possible.

This study is independent research funded by the National Institute for Health Research Yorkshire and Humber ARC, reference NIHR200166 and HDRUK grant WP0011. The views expressed in this publication are those of the author(s) and not necessarily those of the NHS or funders. The funders had no role in study design, data collection and analysis, or preparation of this blog post.


  Type 1 EDs are those which include consultant-led, multi-specialty 24-hour services with full resuscitation facilities and designated accommodation for the reception of ED patients


Jen Lewis, Richard Jacques, Rebecca Simpson, Madina Hasan, Susan Croft, Simone Croft, Ross McMurray, Suzanne Mason & Regional Linked Data Consortium

20 September 2023