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Risk factors for admission at three urban emergency departments in England: a cross-sectional analysis of attendances over 1 month
  1. Sharif A Ismail1,
  2. Ian Pope2,
  3. Benjamin Bloom3,
  4. Raquel Catalao1,
  5. Emilie Green1,
  6. Rebecca E Longbottom1,
  7. Gwyneth Jansen4,
  8. David McCoy5,
  9. Tim Harris3
  1. 1 Barts Health NHS Trust, London, UK
  2. 2 Homerton University Hospital NHS Foundation Trust, London, UK
  3. 3 Emergency Department, Royal London Hospital, London, UK
  4. 4 Queen Mary University of London, London, UK
  5. 5 Centre for Primary Care and Public Health, Queen Mary University of London, London, UK
  1. Correspondence to Dr Ian Pope; ianpope{at}


Objective To investigate factors associated with unscheduled admission following presentation to emergency departments (EDs) at three hospitals in England.

Design and setting Cross-sectional analysis of attendance data for patients from three urban EDs in England: a large teaching hospital and major trauma centre (site 1) and two district general hospitals (sites 2 and 3). Variables included patient age, gender, ethnicity, deprivation score, arrival date and time, arrival by ambulance or otherwise, a variety of ED workload measures, inpatient bed occupancy rates and admission outcome. Coding inconsistencies in routine ED data used for this study meant that diagnosis could not be included.

Outcome measure The primary outcome for the study was unscheduled admission.

Participants All adults aged 16 and older attending the three inner London EDs in December 2013. Data on 19 734 unique patient attendances were gathered.

Results Outcome data were available for 19 721 attendances (>99%), of whom 6263 (32%) were admitted to hospital. Site 1 was set as the baseline site for analysis of admission risk. Risk of admission was significantly greater at sites 2 and 3 (adjusted OR (AOR) relative to site 1 for site 2 was 1.89, 95% CI 1.74 to 2.05, p<0.001) and for patients of black or black British ethnicity (AOR 1.29, 1.16 to 1.44, p<0.001). Deprivation was strongly associated with admission. Analysis of departmental and hospital-wide workload pressures gave conflicting results, but proximity to the “4-hour target” (a rule that limits patient stays in EDs to 4 hours in the National Health Service in England) emerged as a strong driver for admission in this analysis (AOR 3.61, 95% CI 3.30 to 3.95, p<0.001).

Conclusion This study found statistically significant variations in odds of admission between hospital sites when adjusting for various patient demographic and presentation factors, suggesting important variations in ED-level and clinician-level behaviour relating to admission decisions. The 4-hour target is a strong driver for emergency admission.

  • Emergency admission
  • Unscheduled admission
  • Emergency department
  • Emergency service

This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:

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  • Contributors IP, DM and TH initiated the project, designed the study and specified the data collection protocol. IP, RC, EG, REL and GJ collected the data. SAI cleaned and transformed the data, incorporated new variables and performed the statistical analysis. SAI and IP drafted and revised the manuscript. DM, BB and TH commented on and revised the manuscript. TH is the guarantor of this study.

  • Funding None.

  • Competing interests None declared.

  • Ethics approval This study was reviewed by the host Trust Research and Development Board. As there were no deviations from usual care, no interventions, no medications and data were both retrospective and were anonymised,no formal IRAS application was required. The study was registered in accordance with Trust guidelines and governance procedures.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Data sharing statement Extra data can be accessed via the Dryad data repository at with the doi:10.5061/dryad.b1rr1

  • Correction notice This paper has been amended since it was published Online First. Owing to a scripting error, some of the publisher names in the references were replaced with 'BMJ Publishing Group'. This only affected the full text version, not the PDF. We have since corrected these errors and the correct publishers have been inserted into the references.

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