Tag Archives: Weekend effect

Senior Doctors and In-hospital Care

Readers of this News Blog may be aware that we are involved in the HiSLAC (high-intensity, specialist-led acute care) project that examines the impact of increasing consultant presence on acute in-hospital care at weekends.[1-4] Professor Julian Bion, the Principal Investigator for the project, recently drew our attention to two studies from the US that have shown some interesting results in relation to the potential impact of senior doctors on the quality of care. One of the studies was a cross-over randomised controlled trial (RCT) conducted in general medical wards in which increased supervision by attending physicians (senior doctors) was compared with standard supervision [5]; the other was a retrospective cohort study in which the association between physician’s age and patient outcomes was explored.[6]

In the RCT, the attending physicians joined residents and interns (doctors who are still in training) on their ward rounds to see previously admitted (i.e. not newly admitted) patients in the increased supervision group, while the attending physicians were available but did not join the ward rounds in the standard supervision group. Medical error rates did not differ significantly between increased vs standard supervision (91 [95% CI 77 to 104] vs 108 [95% CI 86 to 134] events per 1000 patient-days), but interns (the most junior doctors) spoke significantly less, and both residents and interns felt that they were lessefficient and less autonomous in the ward rounds with increased supervision.[5]

The retrospective cohort study was undertaken using a 20% random sample of Medicare (an US federal health insurance program primarily for elderly people) beneficiaries admitted to hospital with a medical condition and treated by hospitalists (senior doctors specialised in the general care of patients in hospitals). The association between the hospitalists’ age and 30-day mortality, 30-day re-admission and cost of care was explored with statistical adjustment covering patient characteristics, physician characteristics and hospital fixed effects (which essentially allows comparisons be made within hospitals). Adjusted 30-day mortality was found to increase with doctors’ age: 10.8%, 11.1%, 11.3% and 12.1% for ages <40, 40-49, 50-59 and ≥60 respectively. The association appears robust under various sensitivity and subgroup analyses, with an exception that no such association was found among doctors with a high volume of patients. Re-admission rates were similar between doctors’ age groups and costs of care were slightly higher among older doctors.[6]

What should we make out of these findings? For the RCT, the observed effect (reduction in medical errors) was in the expected direction but the study was under-powered (the sample size was powered to detect a 40% relative reduction in error rates vs. 15% actually observed). However, the junior doctors clearly felt qualified to ‘fly solo’. For the observational study, while the association between doctors’ age and care quality and outcomes may require further scrutiny, it is highly speculative. Since an experimental study is not on the cards, cause and effect reasoning must await triangulation of multiple observations across the chain from cause to effect.[7] Such a study is currently under way with respect to the cause of the “weekend effect”.[8]

— Yen-Fu Chen, Principal Research Fellow


  1. Watson SI, Chen YF, Bion JF, Aldridge CP, Girling A, Lilford RJ. Protocol for the health economic evaluation of increasing the weekend specialist to patient ratio in hospitals in England. BMJ Open. 2018; 8: e015561.
  2. Bion J, Aldridge CP, Girling A, et al. Two-epoch cross-sectional case record review protocol comparing quality of care of hospital emergency admissions at weekends versus weekdays. BMJ Open. 2017; 7: e018747.
  3. Chen Y-F, Boyal A, Sutton E, et al. The magnitude and mechanisms of the weekend effect in hospital admissions: A protocol for a mixed methods review incorporating a systematic review and framework synthesis. Syst Rev. 2016; 5(1): 84.
  4. Tarrant C, Sutton E, Angell E, Aldridge CP, Boyal A, Bion J. The ‘weekend effect’ in acute medicine: a protocol for a team-based ethnography of weekend care for medical patients in acute hospital settings. BMJ Open.2017; 7(4): e016755.
  5. Finn KM, Metlay JP, Chang Y, et al. Effect of increased inpatient attending physician supervision on medical errors, patient safety, and resident education: a randomized clinical trial. JAMA Intern Med. 2018; 178(7): 952-59.
  6. Tsugawa Y, Newhouse JP, Zaslavsky AM, Blumenthal DM, Jena AB. Physician age and outcomes in elderly patients in hospital in the US: observational study. BMJ. 2017; 357: j1797.
  7. Lilford RJ, Chilton PJ, Hemming K, Girling AJ, Taylor CA, Barach P. Evaluating policy and service interventions: framework to guide selection and interpretation of study end pointsBMJ. 2010; 341: c4413.
  8. Lilford RJ, Chen YF. The ubiquitous weekend effect: moving past proving it exists to clarifying what causes it. BMJ Qual Saf. 2015; 24(8): 480-2.



Weekend vs. Weekday Care as Viewed Through the Eyes of the Patient

In this news blog we have previously discussed patient’s experiences of hospital care at weekends.[1] Now a paper published in BMJ Quality and Safety has conducted a secondary analysis based on two surveys to determine whether patients treated in hospital had different experiences of care on the weekends compared to weekdays.[2]

These results may surprise you.

The view of patients attending accident and emergency was more favourable over the weekends than over weekdays. Similarly patients admitted on a weekend felt that communication was better than those admitted on weekdays. There was no difference on the various other dimensions of perceived care. Patients admitted at the weekend did not perceive worse care than those admitted on weekdays on any of the dimensions of care described in the paper (including waiting times, cleanliness, information on discharge, and overall experiences). Multiple regression was used to adjust for various factors such as referral route, destination on discharge, ethnicity, sex, age group, or whether or not the questions were answered by the patient or a proxy.

Of course, perceptions of care are only loosely correlated with the technical quality of care.[3] Nevertheless, these data are very interesting and call into question the notion that weekend care is as bad as sometimes claimed.

— Richard Lilford, CLAHRC WM Director


  1. Chen Y-F. Patient’s Experience of Hospital Care at Weekends. NIHR CLAHRC West Midlands News Blog. 12 January 2018.
  2. Graham C. People’s experiences of hospital care on the weekend: secondary analysis of data from two national patient surveys. BMJ Qual Saf. 2018; 27(6): 455-63.
  3. Evans DK & Welander Tärneberg A. Health-care quality and information failure: Evidence from Nigeria. Health Econ. 2018; 27(3): e90-3.

Patient’s experience of hospital care at weekends

The “weekend effect”, whereby patients admitted to hospitals during weekends appear to be associated with higher mortality compared with patients who are admitted during weekdays, has received substantial attention from the health service community and the general public alike.[1] Evidence of the weekend effect was used to support the introduction of ‘7-day Service’ policy and associated changes to junior doctor’s contracting arrangement by the NHS,[2-4] which have further propelled debates surrounding the nature and causes of the weekend effect.

Members of the CLAHRC West Midlands are closely involved in the HiSLAC project,[5] which is an NIHR HS&DR Programme funded project led by Professor Julian Bion (University of Birmingham) to evaluate the impact of introducing 7-day consultant-led acute medical services. We are undertaking a systematic review of the weekend effect as part of the project,[6] and one of our challenges is to catch up with the rapidly growing literature fuelled by the public and political attention. Despite that hundreds of papers on this topic have been published, there has been a distinct gap in the academic literature – most of the published papers focus on comparing hospital mortality rates between weekends and weekdays, but virtually no study have compared quantitatively the experience and satisfaction of patients between weekends and weekdays. This was the case until we found a study recently published by Chris Graham of the Picker Institute, who has unique access to data not in the public domain, i.e. the dates of admission to hospital given by the respondents.[7]

This interesting study examined data from two nationwide surveys of acute hospitals in 2014 in England: the A&E department patient survey (with 39,320 respondents representing a 34% response rate) and the adult inpatient survey (with 59,083 respondents representing a 47% response rate). Patients admitted at weekends were less likely to respond compared to those admitted during weekdays, but this was accounted for by patient and admission characteristics (e.g. age groups). Contrary to the inference that would be made on care quality based on hospital mortality rates, respondents attending hospital A&E department during weekends actually reported better experiences with regard to ‘doctors and nurses’ and ‘care and treatment’ compared with those attending during weekdays. Patients who were admitted to hospital through A&E during weekends also rated information given to them in the A&E more favourably. No other significant differences in the reported patient experiences were observed between weekend and weekday A&E visits and hospital admissions. [7]

As always, some cautions are needed when interpreting these intriguing findings. First, as the author acknowledged, patients who died following the A&E visits/admissions were excluded from the surveys, and therefore their experiences were not captured. Second, although potential differences in case mix including age, sex, urgency of admission (elective or not), requirement of a proxy for completing the surveys and presence of long-term conditions were taken into account in the aforementioned findings, the statistical adjustment did not include important factors such as main diagnosis and disease severity which could confound patient experience. Readers may doubt whether these factors could overturn the finding. In that case the mechanisms by which weekend admission may lead to improved satisfaction Is unclear. It is possible that patients have different expectations in terms of hospital care that they receive by day of the week and consequently may rate the same level of care differently. The findings from this study are certainly a very valuable addition to the growing literature that starts to unfold the complexity behind the weekend effect, and are a further testament that measuring care quality based on mortality rates alone is unreliable and certainly insufficient, a point that has long been highlighted by the Director of the CLAHRC West Midlands and other colleagues.[8] [9] Our HiSLAC project continues to collect and examine qualitative,[10] quantitative,[5] [6] and economic [11] evidence related to this topic, so watch the space!

— Yen-Fu Chen, Principal Research Fellow


  1. Lilford RJ, Chen YF. The ubiquitous weekend effect: moving past proving it exists to clarifying what causes it. BMJ Qual Saf 2015;24(8):480-2.
  2. House of Commons. Oral answers to questions: Health. 2015. House of Commons, London.
  3. McKee M. The weekend effect: now you see it, now you don’t. BMJ 2016;353:i2750.
  4. NHS England. Seven day hospital services: the clinical case. 2017.
  5. Bion J, Aldridge CP, Girling A, et al. Two-epoch cross-sectional case record review protocol comparing quality of care of hospital emergency admissions at weekends versus weekdays. BMJ Open 2017;7:e018747.
  6. Chen YF, Boyal A, Sutton E, et al. The magnitude and mechanisms of the weekend effect in hospital admissions: A protocol for a mixed methods review incorporating a systematic review and framework synthesis. Systems Review 2016;5:84.
  7. Graham C. People’s experiences of hospital care on the weekend: secondary analysis of data from two national patient surveys. BMJ Qual Saf 2017;29:29.
  8. Girling AJ, Hofer TP, Wu J, et al. Case-mix adjusted hospital mortality is a poor proxy for preventable mortality: a modelling study. BMJ Qual Saf 2012;21(12):1052-56.
  9. Lilford R, Pronovost P. Using hospital mortality rates to judge hospital performance: a bad idea that just won’t go away. BMJ 2010;340:c2016.
  10. Tarrant C, Sutton E, Angell E, Aldridge CP, Boyal A, Bion J. The ‘weekend effect’ in acute medicine: a protocol for a team-based ethnography of weekend care for medical patients in acute hospital settings. BMJ Open 2017;7: e016755.
  11. Watson SI, Chen YF, Bion JF, Aldridge CP, Girling A, Lilford RJ. Protocol for the health economic evaluation of increasing the weekend specialist to patient ratio in hospitals in England. BMJ Open 2018:In press.

“We seek him here, we seek him there, Those Frenchies seek him everywhere.”

The notorious weekend mortality effect is every bit as elusive as the Scarlet Pimpernel. Recent studies have delved deeper into the possibility that the weekend effect is an artefact of admission of sicker patients at the weekend than on week days.[1] First, it has been shown that the mortality of all who present to the emergency department (i.e. admitted plus sent home) is the same over the weekend as over the rest of the week.[2] Second, patients who arrive by ambulance are generally much sicker than patients arriving by other means and the proportion who arrive by ambulance is higher over the weekend than over weekdays.[3] When controlling for method of arrival, most of the weekend effect disappears. Most, but not all. This paper provides further evidence that most estimates of the weekend effect are at least overestimates. Through Professor Julian Bion’s HiSLAC Study [4] we are evaluating the effect of weekend admission, not just on mortality, but also on the quality of care and the overall adverse event rate. We will use a Bayesian network to synthesise information across the causal chain and come up with a refined estimate of the effect of weekend admission, not only on mortality, but also on other adverse events.

— Richard Lilford, CLAHRC WM Director


  1. Bray BD, Steventon A. What have we learnt after 15 years of research into the ‘weekend effect’? BMJ Qual Saf. 2017; 26: 607-10.
  2. Aldridge C, Bion J, Boyal A, et al. Weekend specialist intensity and admission mortality in acute hospital trusts in England: a cross-sectional study. Lancet. 2016. 388: 178-86.
  3. Anselmi L, Meacock R, Kristensen SR, Doran T, Sutton M. Arrival by ambulance explains variation in mortality by time of admission: retrospective study of admissions to hospital following emergency department attendance in England. BMJ Qual Saf. 2017; 26: 613-21.
  4. Chen Y, Boyal A, Sutton E, et al. The magnitude and mechanisms of the weekend effect in hospital admissions: A protocol for a mixed methods review incorporating a systematic review and framework synthesis. Syst Rev. 2016; 5: 84.

Another Study of the Effect of Increasing Specialist Availability on Hospital Mortality Rates

News Blog readers will know that a study associated with CLAHRC WM is evaluating the effect on excess mortality among patients admitted over the weekend. This prospective study, led by CLAHRC WM Leadership Fellow Julian Bion, is making use of a ‘natural experiment’ as hospitals increase consultant presence at different rates. A similar study has examined the effect of gradual increase in intensivist staffing in American intensive care units.[1] An association at baseline between intensivist staffing and mortality was found. But hospitals “that adopted intensivist staffing during the study period did not substantially improve their mortality rates.” The relative risk was 0.96 (0.90 – 1.02) on the difference-in-difference measure. An observer with a symmetrical prior centred on a 4% difference in the difference would, of course, be able to cling onto that 4% effect size. If all adverse events were reduced in proportion, would this be cost-effective at the nominal US willingness-to-pay threshold for a year of healthy life of about $100,000. The CLAHRC WM Director feels a modelling study coming on. But here is a back-of-the-envelope calculation. ITU mortality in the US is about 12%.[2] This could be reduced by 4% to about 0.5%, or about five lives in a thousand ITU admissions. That amount to around 50 life years if the mean life expectancy of a life saved is 10 years. Fifty life years represents an (undiscounted) expected benefit of $5,000,000. Any less and the extra intensivists would represent poor value for money.

— Richard Lilford, CLAHRC WM Director


  1. Nagendran M, Dimick JB, Gonzalez AA, Birkmeyer JD, Ghaferi AA. Mortality Among Older Adults Before Versus After Hospital Transition to Intensivist Staffing. Med Care. 2016; 54(1): 67-73.
  2. Zimmerman JE, Kramer AA, Knaus WA. Changes in Hospital Mortality for United States Intensive Care Unit Admissions from 1988 to 2012. Crit Care. 2013; 17: R81.

The Latest Dr Foster Unit Article on the Weekend Effect

More on the weekend effect – this time concerning the CLAHRC WM Director’s speciality, obstetrics. This was another large database study,[1] with an impressive 1.3 million deliveries from the English National Health Service database. The weekend effect is the difference in outcomes from weekend admissions versus weekday admissions. However, the main study finding was that “the perinatal mortality rate was 7.3 per 1000 babies delivered at weekends, 0.9 per 1000 higher than for weekdays (adjusted odds ratio 1.07, 95% confidence interval 1.02 to 1.13)”. But look at the figure and the rate was even higher on a Thursday, and Wednesday and Thursday combined would yield a similar increase over the mean. Granted, weekend was an a priori hypothesis and Thursday was not, but that does not mean we should ignore the observation – the babies who died were not aware of this ‘rule of the game’ in frequentist statistics. The authors make the usual mistake of enumerating preventable deaths on the basis of ‘cause and effect’ assumption. They came up with 770 per year.

By the time the CLAHRC WM Director received the print version of the BMJ, 36 critical comments had already been posted online.

Reinhart and Rogoff made their data of factors associated with economic depressions available to other scientists [2] – the CLAHRC WM Director assumes that Palmer and colleagues will also make their data available for re-analysis?

— Richard Lilford, CLAHRC WM Director


  1. Palmer WL, Bottle A, Aylin P. Association between day of delivery and obstetric outcomes: observational study. BMJ. 2015; 351: h5774.
  2. Reinhart CM & Rogoff K. This Time is Different: Eight Centuries of Financial Folly. Princeton, NJ: Princeton University Press, 2011.

Mortality Following Emergency Surgery – Hospital Level Failure

News Blog readers know that CLAHRC WM has a large interest in factors associated with hospital mortality – partly through a linked NIHR HS&DR grant on mortality following weekend admission, directed by Prof Julian Bion. A recent study of surgical mortality, based on the English Hospital Episode Statistics database, has again found an association between staffing levels (and other facilities) and surgical mortality.[1] The weekend effect was also greater where staffing levels were low. However, as pointed out in a previous post, staffing levels are a proxy for money, and vice-versa. That is to say, the lion’s share of a hospital’s budget goes on staffing; staff salaries are fixed nationally, and so there is not much that a hospital board can do if they are disadvantaged by the reimbursement formula or other unfavourable fixed costs. One thing the hospital board can do is to make sure that expenditure is kept under control so that draconian cuts are not needed downstream. If you want to take care of your patients, take care of your money.

— Richard Lilford, CLAHRC WM Director


  1. Ozdemir BA, et al. Mortality of emergency general surgical patients and associations with hospital structures and processes. Br J Anaesthesia. 2016: 116(1): 54-62.

The Weekend Effect

It is well known that the mortality rate of patients admitted to hospitals over the weekend is higher than that for patients admitted during the week. Whether, or to what extent, this ‘weekend effect’ is caused by case-mix factors vs. care quality factors is one of the big unknowns. This is being investigated by a CLAHRC WM-associated HS&DR grant led by Prof Julian Bion with economic support from Sam Watson, the CLAHRC WM Director and Jo Lord. We were thus provoked by a recent article by Meacock at al [1] investigating the health economics of providing increased consultant support over the weekend. The health gain is calculated on the basis of avoiding all of the excess in deaths and this is offset against the cost of providing a seven-day service. Based on their calculation, the authors find that even if the weekend effect could be eliminated, it would not justify the cost of the service at the NICE willingness-to-pay threshold. In other words, the opportunity cost is such that it would be better to leave the money doing what it is currently doing (if no new money), or to allocate it elsewhere (if new money). However, preventable deaths are merely the top of the adverse event severity pyramid and if the adverse events come down roughly in proportion to deaths, then the gains are much greater and the cost much lower than estimated in the paper. CLAHRC WM collaborators have produced a model to estimate the costs and benefits of reducing adverse events.[2] [3] We hope to collaborate with the authors of the Meacock paper in developing this research.

–Richard Lilford, CLAHRC WM Director


  1. Meacock R, Doran T, Sutton M. What are the costs and benefits of providing comprehensive seven-day services for emergency hospital admissions? Health Economics. 2015. [ePub].
  2. Yao GL, Novielli N, Manaseki-Holland S, Chen Y-F, van der Klink M, Barach P, Chilton PJ, Lilford RJ. Evaluation of a predevelopment service delivery intervention: an application to improve clinical handovers. BMJ Qual Saf. 2012; 21(s1):i29-38.
  3. Lilford RJ, Girling AJ, Sheikh A, et al. Protocol for evaluation of the cost-effectiveness of ePrescribing systems and candidate prototype for other related health information technologies. BMC Health Serv Res. 2014; 14: 314.

Increased Weekend Mortality

The subject of increased weekend mortality for patients admitted over the weekend has been mentioned in this blog previously. This has been attributed to reduced availability of consultants over the weekend. However, a causal link between reduced consultant cover and worse outcomes is unproven. If consultant availability is the main factor behind the weekend effect, then we would expect to see a surge in mortality if consultant presence dropped over the working week. Jena et al. (2015) [1] studied mortality rates of patients admitted for myocardial infarction, cardiac arrest, or heart failure during normal times compared to periods when national cardiology meetings were taking place in the USA. A sizeable proportion of heart specialists down tools to attend the conference. Surprisingly, not only were adjusted 30-day mortality rates not increased, but they were lower among high-risk patients admitted during meetings compared to those admitted at other times. The American College of Cardiology responded by saying they were reassured that during dates of national meetings, patients received care that was no worse than normal. But is the lower risk really reassuring if you are a heart specialist! The CLAHRC WM Director reflects that the premise behind the paper may be wrong and sufficient specialists, or near specialists, stay behind to manage the acute service over the conference period.

— Samuel Watson, Research Fellow


  1. Jena AB, Prasad V, Goldman DP, Romley J. Mortality and Treatment Patterns Among Patients Hospitalized With Acute Cardiovascular Conditions During Dates of National Cardiology Meetings. JAMA Intern Med. 2015; 175(2): 237-44.