Written evidence submitted by Professor Luigi Siciliani, Dr Anastasia Arabadzhyan, Dr James Gaughan, Dr Naomi Kate Gibbs, Professor Susan Griffin, Professor Nils Gutacker, Dr Panos Kasteridis, Dr Maria Ana Matia, Dr Rita Santos, Dr Peter Sivey, Dr Adrian Villaseñor, Professor Simon Walker and Dr Jinglin Wen (NWT0040)

Written evidence submitted by the NIHR Policy Research Unit on the Economics of Health and Social Care Systems and the NIHR Policy Research Unit on Economic Methods of Evaluation in health and care interventions.

1. This written evidence submission summarises literature and empirical studies conducted by the NIHR Policy Research Unit on the Economics of Health and Social Care Systems (ESHCRU) and the NIHR PRU on Economic Methods of Evaluation in health and care interventions (EEPRU). It considers the impact of waiting on health and health inequalities. The evidence can be used to inform the development of waiting times policies, in particular the use of alternative targeted prioritisation of waits for particular procedures or patients. 
2. This document was compiled by Professor Luigi Siciliani from the University of York in consultation with colleagues involved in the relevant research at the Centre for Health Economics: Dr Anastasia Arabadzhyan, Dr James Gaughan, Dr Naomi Kate Gibbs, Professor Susan Griffin, Professor Nils Gutacker, Dr Panos Kasteridis, Dr Maria Ana Matia, Dr Rita Santos, Dr Peter Sivey, Dr Adrian Villaseñor, Professor Simon Walker and Dr Jinglin Wen.
3. Longer waiting times can impact health through different mechanisms: (a) longer waits postpone health benefits from elective care that a patient could have obtained earlier; (b) they potentially reduce patients’ ability to benefit from elective care by making care less effective; and (c) they increase the risk of mortality due to worsening symptoms and deterioration in patient’s health. Differences in waiting times across population groups may also contribute to health inequalities.
4. Current policy in England is that 92% of patients with non-cancerous conditions should wait no longer than 18 weeks from referral to treatment for elective procedures, although this target has not been met recently. A single, universal target is neither equitable nor efficient because it gives the same priority to all patients, independent of their health care needs and their ability to benefit from timely care. Alternative approaches to a single universal target are possible. For instance, patients could be prioritised either across different treatments or within the same treatment, with longer or shorter waits applied differentially. For instance, different waiting time standards could be implemented for different health conditions, as it is already done for cancer care. Clinicians are accustomed to informally prioritise patients, but this could be done more transparently. Although average waiting times systematically differ across treatments according to urgency (for example, waiting times for coronary bypass are much shorter than for a hip replacement), it is possible to devise more formal systems of prioritisation and reflect these in guidance or policy as is done in some other countries.
5. Health benefits lost through longer waiting times. Gibbs et al. (2024a, 2024b, 2025) calculate the effect of an increase in waiting times on patient health for several high-volume elective surgeries: Cataract surgery, Cholecystectomy, Coronary Artery Bypass Graft, Hernia, Hip Replacement, Hysterectomy, Knee Replacement and Percutaneous Coronary Intervention. They estimate the change in Quality-Adjusted Life Years (QALYs) that would arise from a longer waiting time (for example, an additional six weeks of waiting) across ten sub-groups of the population for each procedure defined by sex and deprivation. The model takes account of the postponed health benefit (mechanism (a) above), the risk of dying while waiting (mechanism (c)), the possibility of opting for private sector care while waiting, and the possibility that the capacity to benefit is reduced as a result of a longer wait (mechanism (b)). They find that the largest health loss from waiting an additional six weeks is for hip and knee replacement, driven by the substantial health improvement that these surgeries generate through better mobility and reduced pain. However, prioritising these surgeries for shorter waiting times, e.g. by increasing funding for orthopaedic surgical units, would also potentially increase inequality in quality-adjusted life expectancy in the population, as many people waiting for these procedures are older and live in less disadvantaged areas. In general, a universal reduction in waiting time across procedures was estimated to improve population health but increase health inequalities. Targeting waiting time reduction at groups who live in more deprived areas was estimated to mitigate this increase in inequality.
6. Reduced ability to benefit through longer waits. Arabadzhyan et al. (2025) test if longer waiting times reduce patients’ ability to benefit from health care leading to worse health outcomes. If they do, the health loss due to the postponement of the health benefit will be exacerbated. The study focuses on patients who require a Coronary Artery Bypass Graft (CABG) or a Percutaneous Coronary Intervention (PCI). They find that longer waiting times do not lead to worse health outcomes during the pre-pandemic period for these procedures. However, during the pandemic, when waiting times increased substantially, an increase in waiting times for CABG increased the risk of death within 30 days of hospital admission for surgery, and the effect was larger among older patients and for people from disadvantaged backgrounds. No effect was found for PCI. 
7. Waiting according to health need. Kasteridis et al. (2023) investigate the extent to which patients requiring a hip replacement are prioritised on the waiting list based on criteria such as the degree of pain and lack of mobility (within treatment prioritisation). The study provides evidence of modest prioritisation in the length of wait from the time a specialist adds the patient to the waiting list to when they are treated, such that patients with more severe symptoms are treated more quickly (in line with an earlier study by Gutacker at al., 2016). It shows that prioritisation is used more extensively when waiting times are longer, both before and during COVID-19. It also simulates the effect of a ‘stronger’ prioritisation policy, further reducing the wait for patients in more pain or who are less mobile, while increasing the wait for those with less pain and more mobility. The study shows that this stronger prioritisation policy could lead to larger health gains from surgery for those with more severe symptoms.
8. Inequalities in waiting times. Previous studies find that, within publicly funded systems, patients who are financially better off have shorter waits than more deprived patients for elective treatments such as hip replacement and CABG. However, waits are generally shorter for cancer treatment and Matias et al. (2024) test for the presence of inequalities in waiting times by socioeconomic status for patients receiving breast cancer surgery (mastectomy or breast conserving surgery). The study finds no evidence that waiting times differed by income deprivation before the pandemic, but those from more disadvantaged backgrounds waited slightly longer (less than a day) during COVID-19. Wen et al. (2024) focus on surgery for prostate cancer. The study finds no differences in waiting times by income deprivation either before or after COVID-19. However, the number of prostate surgeries for patients living in the most income-deprived areas is substantially lower than for those living in the least deprived areas, both before and after COVID-19. Previous work by Moscelli et al. (2018) shows that waiting time inequalities by income deprivation for coronary bypass are larger in the years when waiting times were longer. 
9. Effects of increases in diagnostic capacity on diagnostic waiting times. Sivey and Wen (2024) test the impacts of community diagnostic centres (CDCs) on volume and waiting times in the NHS Trusts where they opened. The results show that CDCs were associated with substantial increases in the volume of tests (a six to 13 percentage point increase), mainly driven by CDCs located in more income-deprived areas.  However, there was no evidence of a fall in the share of patients waiting more than six weeks. This could be explained by the time lag between volume increase and a fall in waiting time and an expansion of demand associated with the opening of new facilities.
10. There is scope for the NHS to enhance waiting time prioritisation both across and within treatments to minimise the health loss while patients are waiting on the list.

Disclaimer

This document summarises independent research funded by the National Institute for Health and Care Research (NIHR) Policy Research Programme (PRP), conducted through the NIHR Policy Research Unit in Economics of Health Systems and Interface with Social Care (ESHCRU, grant reference PR-PRU-1217–20,301) and the NIHR Policy Research Unit in Economic Evaluation of Health and Care Interventions (EEPRU, grant reference PR-PRU-1217–20,401). The views expressed are those of the authors and not necessarily those of the NIHR or the Department of Health and Social Care.

References

Arabadzhyan, A., Santos, R., and Siciliani, L., 2025. The effect of waiting times on health outcomes for coronary bypass and angioplasty, Journal of Economic Behaviour & Organization, in press. 

Gibbs, N.K., Griffin, S., Gutacker, N., Villaseñor, A. and Walker, S., 2025. Prioritizing Patients from the Most Deprived Areas on Elective Waiting Lists in the NHS in England: Estimating the Health and Health Inequality Impact. MDM Policy & Practice, 10(1), p.23814683241310146.

Gibbs, N.K., Griffin, S., Gutacker, N., Villaseñor, A. and Walker, S., 2024a. Elective surgery waiting time prioritisation to improve population health gains and reduce health inequalities. EEPRU Report.

Gibbs, N.K., Griffin, S., Gutacker, N., Villaseñor, A. and Walker, S., 2024b. The Health Impact of Waiting for Elective Procedures in the NHS in England: A Modeling Framework Applied to Coronary Artery Bypass Graft and Total Hip Replacement. Medical Decision Making, p.0272989X241256639.

Gutacker, N., Siciliani, L. and Cookson, R., 2016. Waiting time prioritisation: Evidence from England. Social Science & Medicine, 159, pp.140-151.

Kasteridis, P., Siciliani, L. and Sivey, P., 2023. Waiting time prioritisation in the health sector: Evidence from hip replacement surgery. CHE Research Paper 194. Centre for Health Economics, University of York.

Matias, M.A., Santos, R., Siciliani, L., Sivey, P. and Proctor, A., 2024. Socioeconomic inequalities in waiting times for breast cancer surgery. Health Economics. 34(2), 203–224.

Moscelli, G., Siciliani, L., Gutacker, N. and Cookson, R., 2018. Socioeconomic inequality of access to healthcare: Does choice explain the gradient? Journal of Health Economics, 57, pp.290-314.

Sivey, P., and Wen, J. 2024. The effect of community diagnostic centres on volume and waiting time for diagnostic procedures in the UK. Health policy, 147, 105101.

Wen, J., Santos, R., Siciliani, L. and Proctor, A., 2024. Socioeconomic inequalities in hospital access for prostate cancer before and after COVID-19. Socio-Economic Planning Sciences, 94, p.101914.