Surgical hubs: key to tackling hospital waiting lists?

Our evaluation provides evidence that NHS elective surgical hubs can significantly increase treatment volumes and improve efficiency, which could help reduce the elective care waiting list. 

In June 2024, out of 7.6 million cases on the waiting list for consultant-led care, 1.2 million were for people waiting for admission to hospital for elective surgical treatment. These people – waiting for operations such as hip replacements or cataract surgeries – tend to have waited longer than those on the rest of the waiting list, often in avoidable discomfort and pain. As the new government pledges to ‘clear’ the waiting list backlog within 5 years, tackling waits for this group of people should be a priority.

Most elective services are carried out in acute hospitals that also treat large numbers of emergency patients. This means that surges in demand for emergency care – such as during the pandemic or in a bad winter – can lead to cancellations of planned surgeries given the need to prioritise more urgent, unplanned work. 

Elective surgical hubs play a pivotal role in NHS England’s plans to tackle the elective care backlog. Surgical hubs aim to improve productivity, reduce cancelled operations and enable people to be discharged from hospital more quickly. These specialised ‘hospitals within a hospital’ are dedicated to planned surgeries using ringfenced staff and resources. This effectively separates elective care into two pathways: a hub focusing on high-volume low-complexity (HVLC) cases, such as cataract removal, tonsillectomy or hip replacement, and the rest of theatre space freed up for more complex cases. 

In May 2021, Getting it Right First Time (GIRFT), a national NHS England programme, introduced the HVLC programme to support surgical hubs to adopt best clinical and operational practice. £1.5bn has been invested to drive their expansion, with the creation of 47 new hubs and 26 expanded hub sites between 2023 and 2025. As of September 2024, there were 108 surgical hubs operating across the country with a further 26 due to open by the end of 2025. 

Assessing the impact of health interventions is crucial to ensure they are effective and efficient, particularly in this case given the increasing number of hubs and considerable investment in new sites. The GIRFT team asked the Health Foundation’s Improvement Analytics Unit to undertake the first national evaluation on the impact of elective surgical hubs. Here we explore our findings and the implications for the new government. 

How did we design our evaluation?

Evaluating elective surgical hubs was challenging given diverse hub types, their length of time since opening and different operational contexts. However, all hubs are brought together by GIRFT under a common framework of standards to promote best practice in order to achieve their full impact. GIRFT wanted to know whether having a hub delivered trust-wide improvement in elective activity. Future evaluations will look more closely at how hub design and operation affect productivity and efficiency.

We used the Hospital Episode Statistics dataset on surgeries taking place at NHS acute hospital trusts between April 2018 and December 2022. To mitigate the unique impact of the pandemic, we excluded the 12-month period from April 2020 to March 2021 during UK government COVID-19 lockdowns when elective activity was halted or reduced. We divided trusts into three categories: trusts with well-established hubs predating the pandemic; those opening new hubs just before or in response to it; and those without a hub. For established-hub trusts, we aimed to determine if having an established hub better positioned the trust for elective care recovery post-pandemic. For new-hub trusts, we sought to understand the impact of the new hub on elective activity during its first year. 

To evaluate the impact of surgical hubs on activity, we needed to understand what would have happened to activity in the trusts if they had not had a hub. Comparing actual outcomes at units with an intervention to a hypothetical scenario without the intervention is called a counterfactual analysis. This kind of analysis establishes a clear causal link. Without a counterfactual, we wouldn't know if a change in activity was caused by the hubs or unrelated factors, such as strike action or a flu outbreak. To generate our counterfactuals, we used a novel synthetic control model.

Elective surgical hubs had a positive impact on elective activity 

Figure 1 shows that the counterfactual closely matched the average elective activity at established-hub trusts until the end of the second wave of COVID-19 in April 2021. The impact of hubs on post-pandemic recovery is the difference between the counterfactual’s estimated growth and the established hub trusts’ real growth. Our estimate shows that recovery of elective activity after April 2021 at the 23 established-hub trusts was 11.2% greater for both total and HVLC elective activity compared with the counterfactual. 

To put this in perspective, this means that these trusts, which serve approximately 17% of England’s population, performed 51,086 more procedures (with an uncertainty ranging from 5,523 to 98,030) than expected between April 2021 and March 2022. As well as delivering more operations, we also found that patients stayed in the hospital for shorter periods suggesting that hubs could make elective care more efficient overall.  

At the 31 new-hub trusts, which serve almost a quarter of England’s population, HVLC elective activity was 21.9% higher in the first year of hub opening compared with the counterfactual, with effects apparent after 3 months (Figure 2). This is equivalent to 29,182 more procedures (with an uncertainty ranging from 15,449 to 42,915) than expected per year at these trusts.  

There are some limitations to our study, discussed in detail in the published full report. But these findings support the continued implementation and expansion of hubs to tackle elective care backlogs and should play a role in influencing future NHS policies and funding decisions about the hub model. 

Implications

Our evaluation provides the first robust causal evidence that NHS elective surgical hubs can increase elective hospital activity. It suggests that hubs could play a valuable role in the mix of interventions to tackle hospital waiting lists – a key priority highlighted by Wes Streeting MP in his first statement as newly-appointed health secretary. Considered alongside other research, this evidence has the potential to make a valuable contribution to policymaking as government and NHS leaders seek solutions to the elective care waiting times. 

This kind of evaluation – using a counterfactual to isolate the true effects of an intervention from other changes that might have been happening coincidentally – is crucial for robust impact assessment. Our work provides independent evidence that government policymakers can use to make evidence-based policy decisions. By using and showcasing novel methods that remain relatively uncommon in health policy research, our work also provides insights to other researchers looking to apply and tailor these methods for their own analyses.