Ups and downs: what's next for the NHS waiting list?

The waiting list for routine procedures in England totalled 7.5 million in February 2024, the lowest it has been since summer 2023. Does this mean the NHS has turned a corner? 

Last year, we published analysis looking at the waiting list up until August 2023 and projected when it might peak by modelling referrals, treatments and strike action. Based on these, we expected the waiting list to continue to grow before peaking in summer this year. However, since September last year, there has been a consistent decrease in the waiting list – the biggest 5-month fall since the COVID-19 pandemic, even allowing for recording changes that meant the waiting list was essentially flat between January and February this year. 

What has happened to the size of the waiting list?

The waiting list was increasing long before the pandemic and rose from 3.01 million in February 2014 to 7.54 million in February this year. As the waiting list has increased, there has been a corresponding increase in the time people wait to start treatment. For people currently waiting to start treatment, only 57.6% have been waiting for less than 18 weeks, compared with 93.4% in February 2014. The current figure is far below the 18-week referral-to-treatment standard of 92% enshrined in the NHS Constitution. While the pandemic impacted both the number of people waiting and waiting times, a decade of underinvestment in the NHS and other public services, chronic staff shortages and longstanding neglect of adult social care have also contributed to the two-and-a-half-fold increase in the waiting list since 2014.

Tackling the backlog of elective care has been a key government priority for a number of years. In February 2022, NHS England published an elective recovery plan outlining ambitions to eliminate very long waits. This was followed by the Prime Minister making cutting the waiting list one of the five key priorities for 2023. Despite this sustained policy attention, the waiting list grew continuously until September 2023 when it reached 7.8 million, after which it started to decrease. The waiting list remains higher than its level at the time of the Prime Minister’s pledge.

Industrial action over the past year, by both junior doctors and consultants, is often suggested as the key reason further progress hasn’t been made on reducing the waiting list. However, our analysis estimated that between March and October 2023, industrial action by hospital doctors was responsible for approximately 210,000 missed completed pathways (the outflow of people off the waiting list). This accounted for just over half of the growth in the waiting list over this period but is a tiny fraction (less than 3%) of the overall size of the waiting list. For the most recent junior doctor strikes in December 2023 and January and February 2024, we estimate another approximately 58,000 missed completed pathways. 

What explains the fall in the waiting list since September?

The waiting list decreases when the number of completed pathways exceeds the total number of referrals onto the waiting list. Because this has happened each month since September, the waiting list has fallen. This is not unexpected, as the waiting list generally falls over the winter months due to fewer referrals than completed pathways before rising again when referrals go back to previous levels. This seasonal variation occurs naturally throughout the year – for example, referrals are often lower over winter months in response to increased pressure in hospitals and a lack of capacity to treat elective patients. 

Figure 2 shows both referrals and completed pathways adjusted for seasonal changes per working day, as well as the projections we made in October 2023 based on trends up to August 2023. Referrals in 2022/23 were still below pre-pandemic levels and only started consistently exceeding pre-pandemic levels from spring 2023. Our projections estimated that the number of referrals would continue to grow at the same rate as in the post-pandemic recovery period. However, from October last year, the number of referrals has been consistently lower than projected and is similar to pre-pandemic levels. 

It’s not clear why referrals are not growing as expected. One possible reason is that our projections included some of the ‘missing patients’ not referred during the pandemic belatedly coming forward, and referrals have now dropped back down following this temporary spike – although it seems unlikely this would happen uniformly across England. Another possible reason cited by some commentators is an increased use of advice and guidance, a service that provides primary care clinicians with specialist advice. However, national data suggest that the number of advice and guidance diversions per working day has also fallen. Other possible reasons for lower than expected referral numbers include the pressure on primary care services, people’s ability to see a GP and the potential difficulties of referring new patients into secondary care due to capacity constraints, all of which could lead to changes in referral behaviour. Further analysis is required to fully understand what might be driving changes to the number of referrals.

Completed pathways throughout 2022/23 were lower than pre-pandemic levels, and it is only in recent months that we’ve seen activity reach or exceed pre-pandemic levels. The growth in completed pathways has been marginally lower compared with the base case projections we made in October 2023. However, this falls within the level of variation we would have expected. It may also be a result of the wider and longer-term impacts of industrial action such as financial constraints on trusts. A pay deal was recently reached with consultants, however, junior doctors are still in dispute over pay and have a fresh mandate for a further 6 months of industrial action. With ongoing strikes, the system is likely to continue to struggle to increase elective care activity. 

What happens next?

Following recent declines, it is tempting to think the waiting list has now peaked and will continue to decrease. However, the recent fall has been largely driven by lower than expected referrals – plus recent reporting changes for community services pathways – rather than significantly higher numbers of completed pathways. How the waiting list changes over the coming months will be determined by whether the drop in referrals reflects a genuine and sustained decrease in demand or a temporary suppression that could bounce back at any time – a continued decrease in the waiting list due to fewer referrals will raise questions about whether people are accessing the care they require. It will also depend on whether the growth in completed pathways can be sustained despite continued strike action. The uncertainty around both of these factors means that what happens next is unclear. While the recent progress in addressing the backlog is very welcome, it is too early to determine whether the NHS has turned a corner in its efforts to bring down the waiting list and how the reductions are being achieved.