Evidence map›Paper›PMID 41974544›Full record

ArticleBMJ open2026

Days alive and out of hospital after burr-hole drainage for chronic subdural haematoma: a national cohort study using Hospital Episode Statistics in England.

Daniel Thompson, Adam Wahba, Benjamin Davies, Adam Williams, Peter John Hutchinson, Daniel Stubbs, Adel Helmy, David A Cromwell

Abstract read
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Article in BMJ open, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

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2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

8 authors.

Daniel ThompsonDepartment of Clinical Neurosciences, University of Cambridge, Cambridge, UK dt558@cam.ac.uk.ORCID http://orcid.org/0009-0002-4140-1452
Adam WahbaDepartment of Neurosurgery, Royal Hallamshire Hospital, Sheffield, UK.ORCID http://orcid.org/0000-0001-5746-0129
Benjamin DaviesDepartment of Clinical Neurosciences, University of Cambridge, Cambridge, UK.
Adam WilliamsDepartment of Neurosurgery, NHS North Bristol NHS Trust, Bristol, UK.
Peter John HutchinsonDepartment of Clinical Neurosciences, University of Cambridge, Cambridge, UK.ORCID http://orcid.org/0000-0002-2796-1835
Daniel StubbsPerioperative, Acute, Critical, and Emergency Care Section, Department of Medicine, University of Cambridge, Cambridge, UK.ORCID http://orcid.org/0000-0003-2778-5226
Adel HelmyDepartment of Clinical Neurosciences, University of Cambridge, Cambridge, UK.
David A CromwellDepartment of Health Services Research and Policy, London School of Hygiene & Tropical Medicine, London, UK.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

objectivesThe objective of this study was to investigate the utility of the days alive and out of hospital (DAOH) metric within a cohort of patients undergoing burr-hole drainage of a chronic subdural haematoma (CSDH). We evaluate the validity of the DAOH metric in a national CSDH cohort and examine how the DAOH metric compares to its constituent outcomes (mortality and hospital bed days) at an organisational level.

methodsRetrospective cohort study using Hospital Episode Statistics data linked to the national death registry to identify patients who underwent burr-hole drainage of CSDH in English National Health Service neurosurgical units between 1 April 2013 and 31 March 2020. Construct validity was assessed by measuring the patterns of DAOH across categories of known perioperative risk factors. Variation between units in the risk-adjusted values for DAOH, postoperative mortality and days in hospital was explored using funnel plots. Linear regression and logistic regression were used to derive the risk-adjusted rates.

resultsOverall, 16 450 patients who underwent at least one burr-hole drainage of CSDH were identified during the time period. The median 30-day DAOH was 16 (IQR, 0-24); the median for the 90-day DAOH was 74 (42-84), and was better at measuring the complete stay associated with the index admission. Worse 90-day DAOH values were associated with older age, increasing comorbidities and greater frailty. Risk-adjusted 90-day DAOH values for neurosurgical units varied more markedly than for its constituent outcomes.

conclusionsThe 90-day DAOH looks to be a valid outcome metric for patients undergoing burr-hole drainage for CSDH that is feasible to derive using national hospital data. Future work should explore how to estimate a minimally important clinical difference for DAOH and evaluate its utility as an outcome measure.

Indexed as

DrainageHematoma, Subdural, ChronicLength of StayTrephiningAgedAged, 80 and overEnglandFemaleHumansMaleMiddle AgedRetrospective StudiesRisk FactorsHealth EquityHealth policyLongitudinal studiesNeurosurgeryRisk Factors

Identifiers

PMID41974544
PMCPMC13084945

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.