Weekly variation in health-care quality by day and time of admission: a nationwide, registry-based, prospective cohort study of acute stroke care

SSNAP collaboration

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Background Studies in many health systems have shown evidence of poorer quality health care for patients admitted on weekends or overnight than for those admitted during the week (the so-called weekend effect). We postulated that variation in quality was dependent on not only day, but also time, of admission, and aimed to describe the pattern and magnitude of variation in the quality of acute stroke care across the entire week. Methods We did this nationwide, registry-based, prospective cohort study using data from the Sentinel Stroke National Audit Programme. We included all adult patients (aged >16 years) admitted to hospital with acute stroke (ischaemic or primary intracerebral haemorrhage) in England and Wales between April 1, 2013, and March 31, 2014. Our outcome measure was 30 day post-admission survival. We estimated adjusted odds ratios for 13 indicators of acute stroke-care quality by fitting multilevel multivariable regression models across 42 4-h time periods per week. Findings The study cohort comprised 74 307 patients with acute stroke admitted to 199 hospitals. Care quality varied across the entire week, not only between weekends and weekdays, with different quality measures showing different patterns and magnitudes of temporal variation. We identified four patterns of variation: a diurnal pattern (thrombolysis, brain scan within 12 h, brain scan within 1 h, dysphagia screening), a day of the week pattern (stroke physician assessment, nurse assessment, physiotherapy, occupational therapy, and assessment of communication and swallowing by a speech and language therapist), an off-hours pattern (door-to-needle time for thrombolysis), and a flow pattern whereby quality changed sequentially across days (stroke-unit admission within 4 h). The largest magnitude of variation was for door-to-needle time within 60 min (range in quality 35–66% [16/46–232/350]; coefficient of variation 18·2). There was no difference in 30 day survival between weekends and weekdays (adjusted odds ratio 1·03, 95% CI 0·95–1·13), but patients admitted overnight on weekdays had lower odds of survival (0·90, 0·82–0·99). Interpretation The weekend effect is a simplification, and just one of several patterns of weekly variation occurring in the quality of stroke care. Weekly variation should be further investigated in other health-care settings, and quality improvement should focus on reducing temporal variation in quality and not only the weekend effect. Funding None.

Original languageEnglish
Pages (from-to)170-177
Number of pages8
JournalThe Lancet
Issue number10040
Publication statusPublished - 9 Jul 2016
Externally publishedYes

Bibliographical note

Funding Information:
The Sentinel Stroke National Audit Programme (SSNAP) is funded by the Healthcare Quality Improvement Partnership on behalf of National Health Service (NHS) England. The study received no specific funding, but some of the authors are funded either fully or partly. BDB is supported by the National Institute for Health Research (NIHR) as an academic clinical fellow. MAJ is supported by the NIHR Collaboration for Leadership in Applied Health Research and Care for the South West Peninsula. CDAW acknowledges financial support from the NIHR Biomedical Research Centre based at Guy's and St Thomas' NHS Foundation Trust and King's College London, the Stanley Thomas Johnson Foundation, the Stroke Association, and NIHR Programme Grant funding. HH is supported by awards establishing the Farr Institute of Health Informatics Research from the Medical Research Council (reference MR/K006584/1), in partnership with Arthritis Research UK, the British Heart Foundation, Cancer Research UK, the Economic and Social Research Council, the Engineering and Physical Sciences Research Council, NIHR, the National Institute for Social Care and Health Research (Welsh Assembly Government), the Chief Scientific Office (Scottish Government Health Directorates), and the Wellcome Trust. We thank the many hundreds of individuals and organisations participating in the SSNAP, without whose efforts this study would not be possible. On behalf of everyone who has contributed to the project, we thank the clinical leads at each participating site and the individuals in the Royal College of Physicians Stroke Programme involved in coordinating data collection, whose names are available online ( www.rcplondon.ac.uk/projects/outputs/ssnap-collaboration ).

Publisher Copyright:
© 2016 Elsevier Ltd


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