Evaluation of the Impact of High-Intensity Specialist-Led Acute Care (HiSLAC) on Emergency Medical Admissions to NHS Hospitals at Weekends

Timescale: 2014 - 2019

Funder: NIHR

Key points

  • Emergency medical patients admitted to hospitals at weekends have poorer outcomes than those admitted during the week.
  • This research is important because it offers a unique opportunity to evaluate the impact of the transition to seven-day working, and to understand factors likely to impede or enhance the effectiveness of this change in practice.


This study aims to evaluate High-Intensity Specialist-Led Acute Care (HiSLAC) to improve the care of acutely ill medical patients admitted as emergencies to English hospitals at weekends. In the first stage, metrics for HiSLAC will be produced, and levels of ‘penetration’ mapped. The second stage of the study will examine the impact of HiSLAC through an NHS-wide comparison of HiSLAC penetration with NHS performance and outcomes. Alongside this, a detailed quantitative and qualitative study of 10 HiSLAC and 10 low-intensity (LoSLAC) hospitals will be conducted involving case note reviews of quality of care and on-site ethnographic exploration of approaches, barriers, and facilitators to HiSLAC.

The research study

Researchers from SAPPHIRE are conducting qualitative research to find out more about how hospitals organise systems for weekend care in the 20 case study hospitals. Researchers will explore: how care is organised on weekdays and weekends and how this impacts on staff and patients; the reasons for local variation between hospitals in the way weekend care is organised; and the barriers and facilitators to implementing high-intensity specialist-led acute care (HiSLAC). Researchers will ‘shadow’ clinical staff as they go about their normal work on weekdays and weekends, attend some meetings at the hospitals, and conduct short interviews with some of the staff and patients. The research team are also undertaking a mixed method review to systematically examine the magnitude and mechanisms of the weekend effect.

Research team

Carolyn TarrantLiz SuttonJanet Willars
Dr Carolyn Tarrant Elizabeth Sutton Dr Janet Willars
Sarah Chew 2016 David Kocman - 2014 Elisa Liberati
Dr Sarah Chew Dr David Kocman Dr Elisa Liberati
Emma Angell
Emma Angell

Further details on the project can be found on the HiSLAC website

Outputs & publications

Tarrant C, Sutton E, Angell E on behalf of the HiSLAC study, et al 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)

Yen-Fu C, Boyal A, Sutton E, Armoiry X, Watson S, Bion J, Tarrant C, and on behalf of the HiSLAC Collaborative The magnitude and mechanisms of the weekend effect in hospital admissions: A protocol for a mixed method review incorporating a systematic review and framework synthesis. Systematic Reviews

Aldridge C, Bion J, Boyal A, Chen YF, Clancy M, Evans T, Girling A, Lord J, Mannion R, Rees P, Roseveare C, Rudge G, Sun J, Tarrant C, Temple M, Watson S, Lilford R; HiSLAC Collaborative. Weekend specialist intensity and admission mortality in acute hospital trusts in England: a cross-sectional study. Lancet.

Research finds no association between weekend staffing levels and patient mortality - Press Release

The weekend effect in hospitals: Why we need evidence to underpin policy - SAPPHIRE Blog

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