The performance of the NHS has featured prominently in the current election campaigns for the Scottish Parliament and the Welsh Senedd. This has included various claims about referral to treatment times (RTT) and waiting times statistics that measure waiting times for patients, from consultant‑led referral through to elective treatment.
In recent weeks, this debate has included several high-profile claims comparing RTT performance between the countries of the UK, made by senior politicians and widely reported in the media. An example includes the Secretary of State for Health and Social Care who claimed on 12 April that “The number of patients waiting longer than TWO YEARS for treatment is almost 30 times higher in Scotland than in England”. The same day, the Scottish Labour leader stated in a television debate that “How many people in Scotland are waiting more than two years? 5,000. In England, ten times the size, its 300”; this claim was the subject of an article by BBC Verify. These are similar to claims which OSR investigated and reported publicly on in January 2026 (Chair to Michael Shanks MP) and March 2026 (Chair to Michael Marra MSP).
We know that many users want to be able to compare NHS performance across the UK and that it is frustrating for them when they are unable to do so. The following statement sets out the risks and appropriate uses of statistics on NHS performance in Wales and Scotland, focussing on RTT waiting times.
Comparisons between health systems in the UK
Healthcare in the UK is a devolved matter, meaning that the NHS in each constituent country operates under differing legislative frameworks, policies and priorities, commissioning processes and data systems. This can make it challenging to produce comparable statistics on the performance of the NHS in England, Scotland, Wales and Northern Ireland. The Office for National Statistics (ONS), working with health bodies across the UK, have produced health comparability guidance to help users understand and interpret health statistics to help users avoid drawing misleading conclusions when comparing UK health statistics. They have produced a guide specifically focused on Referral to Treatment (RTT) statistics, noting the following:
- Different waiting lists measure different stages of care, such as referral to treatment, cancer pathways, diagnostics, outpatient appointments, or time spent in emergency departments. These should not be added together to produce an overall total, as this would double-count people who appear on more than one list.
- Health statistics are not fully comparable across the UK. Because healthcare is devolved, England, Wales, Scotland and Northern Ireland operate under different policies, standards and data systems. For example, Wales’ RTT statistics include some non‑consultant‑led pathways that are excluded from England’s headline figures, meaning direct comparisons require careful adjustment and explanation.
- Waiting lists measure demand and activity, not just performance. This means that changes over time, and different rates of change between countries, do not necessarily reflect different levels of performance. They can also reflect capacity, policy changes, population needs and the ongoing effects of the COVID-19 pandemic.
Patient treatment pathways
We have also become aware of claims relating to the RTT data that conflate patient treatment pathways with individual patients. An example of such as claim is in the Reform Wales Senedd Manifesto 2026 where they state: “Approximately 1 in 4 people in Wales are waiting for an appointment.” Similarly, Scottish Labour MP Gregor Poynton claimed in a video posted on his social media accounts that a sixth of Scots are on NHS waiting lists. These figures are incorrectly calculated on the number of open pathways and not the number of individuals waiting for treatment.
In both Wales and Scotland, NHS waiting time statistics are designed to track patient pathways rather than individual people. As a result, a single person may be recorded more than once if they are waiting for more than one appointment or course of treatment at the same time. This means that counts based on treatment pathways, do not necessarily correspond to the number, or proportion, of people waiting for care and should be interpreted accordingly.
Wales
- To support clearer public understanding, Wales have published additional estimates of unique patients waiting to start treatment
- OSR election explainer – health statistics in Wales
Scotland
- Public Health Scotland have produced a blog to help users understand how many patients are waiting for NHS treatment in Scotland
- OSR election explainer – health statistics in Scotland
England
Summary
As shown above, interpreting and making comparisons of health data across the UK can be complex. It is incumbent on all political figures to use data and statistics responsibly and not risk misleading the public, especially on matters of high public interest. We continue to ask that parties and candidates use statistics appropriately and transparently, including by citing their sources and acknowledging any limitations in data. OSR’s Standards for the Public Use of Statistics, Data and Wider Analysis provides further guidance on supporting people to understand statistics when they are used.
You can find further information about this issue, and our explainers on other important topics, on our Elections webpage.
Related links: Health statistics in Wales – Office for Statistics Regulation
Health statistics in Scotland – Office for Statistics Regulation