What are diagnostics, and how are diagnostics services performing?

Diagnostics are tests or procedures used to identify a person’s disease or condition.

Finding out what is wrong with someone is vital to treating them – more than 85% of people seeking NHS care require diagnostics. Prompt diagnosis can save lives (early diagnosis of cancer substantially improves survival rates, for example), saves time and money, and avoids worsening patient outcomes. Diagnostics also have an important role to play in preventive health by improving early detection of illness.

Demand for diagnostics

Demand for diagnostics has been increasing steadily over the past decade as hospital referrals and attendances have risen, and there has been a significant increase since the Covid-19 pandemic. This means more people – 1.6 million in March 2024¹ – are now waiting for diagnostic tests, a 106% increase over the previous decade.

The national target is that 99% of patients should wait less than six weeks for a diagnostic test. This standard has not been met nationally since February 2017 – in March 2024, only 78% of patients received a test in under six weeks.

There is a faster diagnosis standard for cancer, which states that 75% of people who have been urgently referred by their GP for suspected cancer must be diagnosed or have cancer ruled out within 28 days. This was met in March 2024 (77%).

Diagnostic activity

In February 2024, the NHS ran nearly four million diagnostic tests. This is similar to pre-pandemic levels. Pre- and post-Covid-19 activity varies by diagnostic test; of the most frequently performed tests, activity ranges from a 21% fall in fluoroscopies² between February 2020 and February 2024 to a 31% rise in CT scans.

Diagnostic workforce

The diagnostic workforce draws on a wide range of health professionals, from radiologists to nuclear medicine specialists, histopathologists to endoscopists. Staff shortages across the NHS are impacting diagnostics, as the number of people in the workforce has not kept pace with rising demand. There are significant vacancies across all specialities. For example, the Independent Review of Diagnostic Services for NHS England estimated that 3,500 extra radiographers are needed by 2025.

A survey by The Royal College of Radiologists found that the UK has a 29% shortfall of clinical radiologists, which will rise to 40% in five years without action. This shortfall has an impact on staff morale (49% of clinical radiologists report feeling burnt out), retention (the average age of those leaving has dropped from 58 in 2020 to 51 in 2022), and patient safety (only 24% of clinical directors said they had sufficient staff to deliver safe and effective patient care, down from 36% in 2020). Data is not as readily available for other diagnostic professions, but it is safe to assume that shortages exist elsewhere.

The 2023 NHS Long Term Workforce Plan aims to expand the diagnostic workforce, for example, increasing diagnostic radiographer training places from 1,648 in 2022 to 2,300 in 2031, and health care scientist training places (80% of diagnoses require input from a health care scientist) from 776 in 2022 to 1,024 in 2031.

Diagnostic equipment

The UK currently has less diagnostic equipment than comparable countries; in 2020, the UK ranked 25th out of 28 OECD countries for the number of CT, MRI and PET scanners per million population. While there is no ideal number of scanners, this low figure is cause for concern, especially given rising demand – NHS England estimates that demand for CT scans will rise by at least 100% between 2020 and 2025. As well as expanding the supply of diagnostic equipment, some of the existing supply also needs replacing, for example, mobile x-ray machines that are more than 10 years old.

The King's Fund view

Diagnostics have been recognised as a priority to improve NHS performance. In 2021, the government announced the creation of new community diagnostic centres (CDCs) to tackle the waiting list and bring care closer to communities. As of March 2024, 160 CDCs were open and had delivered nearly eight million tests since their inception (though this has further increased pressure on the workforce, and questions have been raised around the proportion of CDCs located in communities instead of on existing hospital sites).

The 2024 Spring Budget included an NHS productivity plan backed by £3.4 billion to invest in NHS technological and digital transformation, including upgrading diagnostic equipment. Research and trials to explore the potential for AI to free up clinical time and improve the accuracy and efficiency of diagnostics are ongoing. This funding and prioritisation are welcome, as without sustained investment, especially in workforce and equipment, any expansion of diagnostics to meet rising demand will be hampered by lack of staff and supplies.