Background
In December 2012 National Health Service (NHS) England published
“Everyone counts: planning for patients 2013/2014” [
1], where plans for seven-day access to NHS services in the United Kingdom were outlined. This led to the establishment of an “
NHS Services, Seven Days a Week” Forum (the “Forum”) chaired by the National Medical Director aimed at initially improving access to diagnostic, urgent and emergency services across the seven-day week.
The need for these changes were argued to be fourfold – to improve excess weekend mortality, to increase cost-efficiency, to move the NHS in line with the retail sector, and to improve the patient “customer” experience [
1‐
3]. The Healthcare Financial Management Association (HFMA) subsequently carried out a costing analysis using a voluntary sample of eight variably sized NHS trusts at different stages of implementation (Table
1) [
2]. Of these, Salford Royal, Aintree University Hospitals, Guy’s & St. Thomas’ and Chelsea & Westminster Hospital NHS Foundation Trusts had already made significant investments prior to the Forum [
2,
4‐
8]. In 2013, both Chelsea & Westminster Hospital and Salford Royal NHS Foundation Trusts reported significant additional changes to seven-day care, whilst Guy’s & St. Thomas’ and County Durham and Darlington NHS Foundation Trusts made more minor changes [
2,
5‐
7,
9]. Similarly, across England, other NHS trusts started reorganising services to reduce the differences in care provision across the seven-day week (full list in Additional file
1: Table S1).
Table 1
List of NHS Foundation Trusts included in the Healthcare Financial Management Association costing analysis, indicating services already available on a seven day basis, services invested in 2013/2014, and the potential costs of further investment in providing seven day care
| Major trauma centre – 24/7 radiology and related trauma support services; seven day a week specialist stroke nurse service | Recruitment of two additional Critical Care Unit consultants (but not in post yet) | £5.8 million | 23 additional consultants, diagnostics, therapies, pharmacy, and nursing |
| Met most clinical standards in all specialties due to previous NHS London audits | 24/7 paediatric consultant cover | £0.4 million | 3 additional consultants |
| Pilot project in A&E & medicine with 6 additional consultants and support services (diagnostics, therapies, pharmacy) | None reported | £3.7 million | 24 additional consultants, therapies, nursing |
| Little investment at assessment – not detailed | Increased Adult Mental Health Liaison services for A&E/ Medical Admissions Units 0800–2200 7 days a week | £6.5 million | 15 additional consultants, diagnostics, therapies, nursing |
| Paediatrics | None reported | £2.1 million | 8 additional consultants, therapies, pharmacy, nursing |
| Already achieved in general medicine & vascular surgery | Improvements in specialist therapy assessment team coverage | – | – |
| Increased consultant coverage in A&E (0800–2400) Emergency Assessment Unit, medical and surgical wards (0800–2000) seven days a week, increased specialist radiology 0800–2400 | Opening of major trauma centre/ “emergency village” with consultant-led care (16 additional consultants) until 8 pm, therapies & pharmacy until 5 pm, seven days a week, 24/7 radiology and pathology, increasing engagement from all departments | £3.2 million | 9 additional specialist consultants |
| Some investment at assessment – not detailed | None reported | £3.5 million | 10 additional consultants, diagnostics, therapies, pharmacy, nursing |
Three years on, various changes to the English NHS, including reformation of consultants’ and junior doctors’ contracts have been deemed necessary for a fully comprehensive seven-day service [
10,
11]. Their basis has been primarily the excess 30-day mortality associated with weekend admissions demonstrated in two analyses of national Hospital Episode Statistics (HES) datasets from 2009 to 2010 and 2013–2014 by Freemantle et al., despite the authors stating it would be “rash and misleading” to attribute this to deficits in service provision [
12,
13]. Given the three-year interval from the original Forum report, we aimed to review changes in clinical outcomes across the English NHS between 2013 and 2016, comparing NHS Trusts that had introduced seven-day changes between 2013 and 2014 and 2014–2015 to those which had not as part of what was essentially a natural intervention study. We aimed to test the null hypothesis that there were no significant differences in outcomes between these two groups during this interval.
Discussion
The three-year lapse from the initiation of the “NHS Services, Seven Days a Week” Forum provided us with an opportunity to analyse outcomes from what was essentially a natural intervention trial involving all English NHS trusts, some of which had redesigned urgent, emergency and some elective services around seven-day working. The finding that for all outcomes studied, trusts instituting seven-day changes did not perform, on average, better than other institutions is unsurprising, particularly as NHS emergency services already operate 24 h a day, seven days a week. Our analysis also did not find any significant improvement in clinical outcomes over time in trusts which had actively reorganised services in 2013–2014 in comparison to those that had not. More worryingly, clinical outcomes such as A&E four-hour breach rates worsened across the English NHS despite approximately half of all trusts instituting seven-day changes.
In some organisations, despite active restructuring of services around seven-day care, there was a worsening or no change in mortality, length of stay and A&E outcomes. The reasons for this are probably multiple. Service reorganisation without sufficient additional investment or a cost-neutral budget could result in weekday care worsening at the expense of increasing weekend service provision so that overall outcomes through the seven-day week are worse or unchanged. Additionally, the association between poorer weekend clinical outcomes and service provision may potentially be non-causal, and therefore increasing weekend services may not result in improvement. Contrastingly, some trusts such as Blackpool Teaching Hospitals NHS Foundation Trust demonstrated reductions in SHMI without significant seven-day reorganisation.
The apparent association between weekend hospitalisation and increased mortality has been repeatedly demonstrated in several studies carried out in different countries [
12,
13,
21‐
23] and healthcare settings [
24]. Other outcomes such as length of stay [
25] and unplanned readmission rates [
26] are also higher for patients admitted over the weekend. However, the definition of what constitutes a “weekday” and the methods of case-mix adjustment in these studies have been variable, [
27] and it is well-recognised that the cause of this association remains unknown. Several factors have been blamed, including reduced availability of senior staff members, diagnostic and support services [
3,
13]. Other possibilities include the fact that sicker patients are more likely to present over the weekend and is incompletely adjusted for by various statistical models, or that publications surrounding the “weekend effect” are systematically biased to detect changes where there are none [
28].
Recent evidence suggests that only 3% of total mortality is avoidable, [
29] and several studies have now emerged suggesting that the “weekend effect” is unlikely to be improved by changes in the level of weekend staffing [
30‐
33]. Our analysis supports this, supporting the assertion that the “weekend effect” is largely due to residual confounding and not care quality. Unlike previous studies which have not successfully determined its cause, [
12,
13,
23] this analysis makes an attempt at dissecting out the effect of widespread reorganisation of clinical services around a seven-day working week on mortality, LOS and A&E quality of care, finding that these outcomes do not largely improve in trusts which have actively done so.
Despite heterogeneity in the measures taken by individual trusts to reorganise services, the changes in clinical outcomes observed between the two periods indicate these measures have also largely not improved such metrics as a whole across the English NHS. More worryingly, outcomes such as A&E four-hour breach rates were significantly worse on a background of increasing A&E attendances, suggesting increasing demands on a service where resources may have been misallocated or insufficient. We postulate therefore that large-scale changes to create a truly “seven-day NHS” such as that proposed (e.g. changes to the definition of unsociable hours working) may not lead to significant improvements, particularly in a cost-neutral setting resulting in limited weekday resources simply being moved to the weekend.
Study limitations
We recognise that our retrospective observational analysis utilising aggregated, trust-level data from publicly available national databases of institutional performance is limited by its quality and resolution, with less capacity for adjustment of confounding to account for differences in case-mix observed at individual trusts. As such, we could only analyse crude mean LOS and A&E outcome metrics at a trust level, and any differences in these outcomes between trusts are still subject to confounding from case-mix variability. Even metrics such as the SHMI, which attempts to account for this by adjusting for comorbidities at an individual patient level using HES data, do not completely adjust for factors such as the severity of a particular comorbidity or socioeconomic status [
34].
Utilisation of aggregated trust-level data also means that there is a risk of over-interpretation at an individual level, a concept known as ecological fallacy. For instance, in this study we categorised trusts as having undergone seven-day service reorganisation on the basis of any increase in seven-day provision to test the hypothesis that this would lead to improvements in clinical outcomes. A patient suffering a stroke on the weekend may have benefitted (reduced mortality risk, reduced length of stay) from some forms of seven-day service reorganisation (such as a 24/7 thrombolysis service) but not others (such as extended weekend pharmacy opening times). However, at a trust level, the limited resolution of data means that determining the clinical effectiveness of specific changes in weekend service provision at an individual level is not possible. In order to do this, further detailed interventional studies need to be undertaken, looking at the effect of a specific change in service on a specific group of patients.
Additionally, individual trusts not included in the initial HFMA costing analysis during the period of interest may not have declared the presence of seven-day service reorganisation accurately via their annual reports. It is possible that some trusts may have demonstrated improved outcomes through such reorganisation that was not formally part of the “NHS Services, Seven Days a Week” project, and the lack of reporting would have diluted any comparative differences in institutional performance. However, it is far more likely that given the centrally-driven push for better seven-day care, any significant changes that could potentially lead to improvements in clinical outcome would have been declared explicitly. The heterogeneity of the various measures taken by individual trusts also means that reorganisation was not uniform; however, one would expect that such a global restructuring of services should at least have resulted in measurable change in clinical outcomes when examined across the entire English NHS. We also recognise that service reorganisation takes time, and that whilst our inclusion of the 2015–2016 analysis period somewhat mitigates for the time lag in the implementation of changes in health policy, further longitudinal analyses should be performed over consecutive years to determine their full effect.
In the pairwise difference in differences analysis of clinical outcomes, we excluded 11 trusts that had undergone significant restructuring by merging with other trusts, as it would have been difficult to determine if any changes were likely to be due to seven-day service reorganisation or the restructuring itself. However, we recognise that merging of trusts may have occurred to improve access to better seven-day services, and it is possible that clinical outcomes in these trusts could have improved as a result of the merge. We have also not examined other outcomes such as patient satisfaction in this analysis, although a similar pilot scheme to extend weekend GP services reported that demand is significantly lower than expected [
35].
Conclusions
Regardless of funding method, all healthcare resources are finite and careful consideration needs to be given with regards to how they are distributed throughout the week. The NHS is predicted to be facing a £30 billion funding gap over the next 5 years, [
36] and it is estimated that an additional £1.07–1.43 billion/ year is required to implement full seven-day emergency hospital services [
37] with a further >£1 billion/ year for seven-day primary care [
38]. A previous health economic analysis has already suggested that moving to comprehensive seven-day services does not fulfill National Institute for Health and Care Excellence (NICE) cost effectiveness criteria, [
37] even if such changes are assumed to lead to improved clinical outcomes such as mortality rates. Whilst our analysis suggests that this may not be the case, its retrospective ecological design is not powered to test this hypothesis definitively. It does however suggest that more detailed prospective interventional studies such as cluster-randomised trials at an institutional or departmental level are still required to determine the aetiology of the “weekend effect”, and governmental health policy and reorganisation of health services aimed at mitigating this should await more solid evidence before being effected.