The cost-effectiveness of diagnostic management strategies for adults with minor head injury
Introduction
Head injury accounts for around 700,000 emergency department (ED) attendances each year in England and Wales,1 90% of which may be categorised as apparently minor on the basis of having a Glasgow Coma Score (GCS) of 13–15 at presentation to hospital.2 The costs of liberal CT scanning and hospital admission are therefore substantial. However, if restriction of investigation and observation leads to delayed treatment of neurosurgical injury then the consequences may be devastating and include death or severe long-term disability.
The main challenge in the management of minor head injury is identification of the minority of patients with significant intracranial injury, especially those who require urgent neurosurgery. Increased access to CT scanning in recent years has reduced the risk of missed pathology but has raised concerns about increased radiation exposure and inappropriate use of health care resources. Clinical decision rules have been developed in an attempt to limit the use of CT scanning whilst limiting the risk of missed pathology.1, 3, 4, 5, 6, 7 It is not clear, however, which existing clinical decision rule achieves the best balance of increasing the benefits of scanning whilst reducing costs and harms, and how these rules compare with CT scanning all, or no patients.
Two previous studies have compared the cost-effectiveness of decision rules but both have limitations.8, 9 One did not include the risk of cancer from CT scans and none were from the perspective of the United Kingdom (UK) National Health Service (NHS). Furthermore, these analyses did not explore decisions beyond CT scanning, such as whether or not to admit a patient with a normal CT scan. Data from the UK have suggested that increased use of CT scanning for minor head injury was associated with increased hospital admission.10 This may be due to admission of patients with non-neurosurgical abnormalities on CT scan or for patients with normal CT scans, but without a responsible adult to observe the patient after discharge.
The goals of this investigation were to: (1) determine the optimal existing CT scanning diagnostic strategy in terms of cost-effectiveness; (2) determine the cost-effectiveness of admission strategies consequent upon CT scanning.
Section snippets
Diagnostic performance of clinical decision rules
A systematic review of the literature was undertaken to evaluate the diagnostic performance of clinical decision rules.11 The literature review identified that most clinical decision rules for adults had estimates of diagnostic parameters from validation cohorts, although often in different settings from the derivation cohort.
Decision rules would be expected to perform better in the derivation cohort and additionally in a validation cohort within the same setting as the derivation cohort.
Deterministic analysis
For adults aged 40, the CCHRhm strategy had an ICER of £3879 when compared to the Scandinavian strategy (the only other strategy on the cost-effectiveness frontier). All other strategies were either dominated or extendedly dominated. For adults aged 75, the CCHRhm strategy had an ICER of £10,397 when compared to the Scandinavian strategy (the only other strategy on the cost-effectiveness frontier). All other strategies were dominated. Although the CCHRhm strategy was estimated to be optimal the
Discussion
Decision-analysis modelling is limited by both the need to make assumptions and the available data. Our estimates of the effect of delayed treatment upon intracranial pathology in particular are based on very limited observational data.
In the UK, hospitals do not collect and record data on the use of resources by individual patients. The process of allocating costs starts with the annual financial returns of a hospital and this expenditure is then reallocated to patient treatment services in a
Conclusions
Our economic analysis confirms that the recent extension of access to CT scanning for minor head injury is appropriate. Liberal use of CT scanning based on a high sensitivity decision rule is not only effective but also cost-saving. It is recommended therefore that all hospitals receiving patients with minor head injury should have unrestricted access to CT scanning for use in conjunction with evidence-based guidelines.
Provisionally the CCHR decision rule appears to be the best strategy
Conflict of interest
The authors have no commercial associations or sources of support that might pose a conflict of interest.
Acknowledgements
This project was undertaken for the UK National Institute for Health Research Health Technology Assessment Program. The findings of this project, including the findings presented in this article, will be published as a report in the Health Technology Assessment monograph series: http://www.hta.ac.uk/project/1765.asp.
The study sponsors had no involvement in the study design; collection, analysis and interpretation of data; the writing of the manuscript or the decision to submit the manuscript
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Economic Evaluation of In-Hospital Clinical Practices in Acute Injury Care: A Systematic Review
2022, Value in HealthCitation Excerpt :$22 660.20; 322.5 noninstitutionalized days alive) was a dominant strategy compared with a 64-slice CT scanner in the radiology department (Int. $23 556.50; 320.7 noninstitutionalized days alive) for trauma patients requiring evaluation,52 and patient-controlled analgesia was dominated by standard care (intravenous morphine) for patients admitted to an inpatient ward with pain from traumatic injuries51 (Table 236-53). We identified 23 interventions of which 6 (26.1%) were found to be more cost-effective than their comparators (Supplemental Digital Content 2 in Supplemental Materials found at https://doi.org/10.1016/j.jval.2021.10.018).
ACR Appropriateness Criteria® Head Trauma: 2021 Update
2021, Journal of the American College of RadiologyCitation Excerpt :There is no relevant literature to support the use ofgs CT in the initial imaging evaluation of mild acute head trauma when imaging is not indicated by a validated clinical decision rule. Mathematical models of quality-adjusted life years gained by 10 diagnostic management strategies in adults with mild head trauma found selective CT scanning with a high-sensitivity clinical decision rule to be effective when compared with “discharge all” or “CT all” strategies [7]. Another analysis calculated a minimum clinical decision rule threshold of 97% sensitivity for the identification of patients with mild head trauma who required neurosurgical intervention in order to outperform “CT all” from a health care system perspective [8].
Traumatic brain injury: Integrated approaches to improve prevention, clinical care, and research
2017, The Lancet Neurology