Conservative management versus invasive management of significant traumatic pneumothoraces in the emergency department (the CoMiTED trial): a study protocol for a randomised non-inferiority trial.

INTRODUCTION: Traumatic pneumothoraces are present in one of five victims of severe trauma. Current guidelines advise chest drain insertion for most traumatic pneumothoraces, although very small pneumothoraces can be managed with observation at the treating clinician's discretion. There remains a large proportion of patients in whom there is clinical uncertainty as to whether an immediate chest drain is required, with no robust evidence to inform practice. Chest drains carry a high risk of complications such as bleeding and infection. The default to invasive treatment may be causing potentially avoidable pain, distress and complications. We are evaluating the clinical and cost-effectiveness of an initial conservative approach to the management of patients with traumatic pneumothoraces. METHODS AND ANALYSIS: The CoMiTED (Conservative Management in Traumatic Pneumothoraces in the Emergency Department) trial is a multicentre, pragmatic parallel group, individually randomised controlled non-inferiority trial to establish whether initial conservative management of significant traumatic pneumothoraces is non-inferior to invasive management in terms of subsequent emergency pleural interventions, complications, pain, breathlessness and quality of life. We aim to recruit 750 patients from at least 40 UK National Health Service hospitals. Patients allocated to the control (invasive management) group will have a chest drain inserted in the emergency department. For those in the intervention (initial conservative management) group, the treating clinician will be advised to manage the participant without chest drain insertion and undertake observation. The primary outcome is a binary measure of the need for one or more subsequent emergency pleural interventions within 30 days of randomisation. Secondary outcomes include complications, cost-effectiveness, patient-reported quality of life and patient and clinician views of the two treatment options; participants are followed up for 6 months. ETHICS AND DISSEMINATION: This trial received approval from the Wales Research Ethics Committee 4 (reference: 22/WA/0118) and the Health Research Authority. Results will be submitted for publication in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: ISRCTN35574247.

A national study of 23 major trauma centres to investigate the effect of a geriatrician assessment on clinical outcomes in older people admitted with serious injury in England (FiTR 2): a multicentre observational cohort study.

BACKGROUND: Older people are at the greatest risk of poor outcomes after serious injury. Evidence is limited for the benefit of assessment by a geriatrician in trauma care. We aimed to determine the effect of geriatrician assessment on clinical outcomes for older people admitted to hospital with serious injury. METHODS: In this multicentre observational study (FiTR 2), we extracted prospectively collected data on older people (aged ≥65 years) admitted to the 23 major trauma centres in England over a 2·5 year period from the Trauma Audit and Research Network (TARN) database. We examined the effect of a geriatrician assessment within 72 h of admission on the primary outcome of inpatient mortality in older people admitted to hospital with serious injury, with patients censored at discharge. We analysed data using a multi-level Cox regression model and estimated adjusted hazard ratios (aHRs). FINDINGS: Between March 31, 2019, and Oct 31, 2021, 193 156 patients had records held by TARN, of whom 35 490 were included in these analyses. Median age was 81·4 years (IQR 74·1-87·6), 19 468 (54·9%) were female, and 16 022 (45·1%) were male. 28 208 (79·5%) patients had experienced a fall from less than 2 m. 16 504 (46·5%) people received a geriatrician assessment. 4419 (12·5%) patients died during hospital stay, with a median time from admission to death of 6 days (IQR 2-14). Of those who died, 1660 (37·6%) had received a geriatrician assessment and 2759 (62·4%) had not (aHR 0·43 [95% CI 0·40-0·46]; p<0·0001). INTERPRETATION: Geriatrician assessment was associated with a reduced risk of death for seriously injured older people. These data support routine provision of geriatrician assessment in trauma care. Future research should explore the key components of a geriatrician assessment paired with a health economic evaluation. FUNDING: None.

The effectiveness and cost-effectiveness of resuscitative endovascular balloon occlusion of the aorta (REBOA) for trauma patients with uncontrolled torso haemorrhage: study protocol for a randomised clinical trial (the UK-REBOA trial).

BACKGROUND: Haemorrhage is the most common cause of preventable death after injury. REBOA is a novel technique whereby a percutaneously inserted balloon is deployed in the aorta, providing a relatively quick means of temporarily controlling haemorrhage and augmenting cerebral and coronary perfusion, until definitive control of haemorrhage can be attained. The aim of the UK-REBOA trial is to establish the clinical and cost-effectiveness of a policy of standard major trauma centre treatment plus REBOA, as compared with standard major trauma centre treatment alone, for the management of uncontrolled torso haemorrhage caused by injury. METHODS: Pragmatic, Bayesian, group-sequential, randomised controlled trial, performed in 16 major trauma centres in England. We aim to randomise 120 injured patients with suspected exsanguinating haemorrhage to either standard major trauma centre care plus REBOA or standard major trauma centre care alone. The primary clinical outcome is 90-day mortality. Secondary clinical outcomes include 3-h, 6-h, and 24-h mortality; in-hospital mortality; 6-month mortality; length of stay (in hospital and intensive care unit); 24-h blood product use; need for haemorrhage control procedure (operation or angioembolisation); and time to commencement of haemorrhage control procedure (REBOA, operation, or angioembolisation). The primary economic outcome is lifetime incremental cost per QALY gained, from a health and personal social services perspective. DISCUSSION: This study, which is the first to randomly allocate patients to treatment with REBOA or standard care, will contribute high-level evidence on the clinical and cost-effectiveness of REBOA in the management of trauma patients with exsanguinating haemorrhage and will provide important data on the feasibility of implementation of REBOA into mainstream clinical practice. TRIAL REGISTRATION: ISRCTN16184981.

Economic Evaluation of In-Hospital Clinical Practices in Acute Injury Care: A Systematic Review.

OBJECTIVES: Underuse of high-value clinical practices and overuse of low-value practices are major sources of inefficiencies in modern healthcare systems. To achieve value-based care, guidelines and recommendations should target both underuse and overuse and be supported by evidence from economic evaluations. We aimed to conduct a systematic review of the economic value of in-hospital clinical practices in acute injury care to advance knowledge on value-based care in this patient population. METHODS: Pairs of independent reviewers systematically searched MEDLINE, Embase, Web of Science, and Cochrane Central Register for full economic evaluations of in-hospital clinical practices in acute trauma care published from 2009 to 2019 (last updated on June 17, 2020). Results were converted into incremental net monetary benefit and were summarized with forest plots. The protocol was registered with PROSPERO (CRD42020164494). RESULTS: Of 33 910 unique citations, 75 studies met our inclusion criteria. We identified 62 cost-utility, 8 cost-effectiveness, and 5 cost-minimization studies. Values of incremental net monetary benefit ranged from international dollars -467 000 to international dollars 194 000. Of 114 clinical interventions evaluated (vs comparators), 56 were cost-effective. We identified 15 cost-effective interventions in emergency medicine, 6 in critical care medicine, and 35 in orthopedic medicine. A total of 58 studies were classified as high quality and 17 as moderate quality. From studies with a high level of evidence (randomized controlled trials), 4 interventions were clearly dominant and 8 were dominated. CONCLUSIONS: This research advances knowledge on value-based care for injury admissions. Results suggest that almost half of clinical interventions in acute injury care that have been studied may not be cost-effective.

Imputation strategies for missing baseline neurological assessment covariates after traumatic brain injury: A CENTER-TBI study.

Statistical models for outcome prediction are central to traumatic brain injury research and critical to baseline risk adjustment. Glasgow coma score (GCS) and pupil reactivity are crucial covariates in all such models but may be measured at multiple time points between the time of injury and hospital and are subject to a variable degree of unreliability and/or missingness. Imputation of missing data may be undertaken using full multiple imputation or by simple substitution of measurements from other time points. However, it is unknown which strategy is best or which time points are more predictive. We evaluated the pseudo-R2 of logistic regression models (dichotomous survival) and proportional odds models (Glasgow Outcome Score-extended) using different imputation strategies on the The Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study dataset. Substitution strategies were easy to implement, achieved low levels of missingness (<< 10%) and could outperform multiple imputation without the need for computationally costly calculations and pooling multiple final models. While model performance was sensitive to imputation strategy, this effect was small in absolute terms and clinical relevance. A strategy of using the emergency department discharge assessments and working back in time when these were missing generally performed well. Full multiple imputation had the advantage of preserving time-dependence in the models: the pre-hospital assessments were found to be relatively unreliable predictors of survival or outcome. The predictive performance of later assessments was model-dependent. In conclusion, simple substitution strategies for imputing baseline GCS and pupil response can perform well and may be a simple alternative to full multiple imputation in many cases.

Healthcare system impacts of the 2017 Manchester Arena bombing: evidence from a national trauma registry patient case series and hospital performance data.

INTRODUCTION: In response to detonation of an improvised explosive device at the Manchester Arena on 22 May 2017, we aimed to use detailed information about injured patients flowing through hospital healthcare to objectively evaluate the preplanned responses of a regional trauma care system and to show how routinely collected hospital performance data can be used to assess impact on regional healthcare. METHODS: Data about injury severity, management and outcome for patients presenting to hospitals were collated using England's major trauma registry for 30 days following hospital attendance. System-wide data about hospital performance were collated by National Health Service England's North West Utilisation Management Unit and presented as Shewhart charts from 15 April 2017 to 25 June 2017. RESULTS: Detailed information was obtained on 153 patients (109 adults and 44 children) who attended hospital emergency departments after the incident. Within 6 hours, a network of 11 regional trauma care hospitals received a total of 138 patients (90%). For the whole patient cohort, median Injury Severity Score (ISS) was 1 (IQR 1-10) and median New ISS (NISS) was 2 (IQR 1-14). For the 75 patients (49%) attending a major trauma centre, median ISS was 7.5 (IQR 1-14) and NISS was 10 (IQR 3-22). Limb and torso body regions predominated when injuries were classified as major life threatening (Abbreviated Injury Scale>3). Ninety-three patients (61%) required hospital admission following emergency department management, with 21 (14%) requiring emergency damage control surgery and 24 (16%) requiring critical care. Three fatalities occurred during early resuscitative treatment and 150 (98%) survived to day 30. The increased system-wide hospital admissions and care activity was linked to increases in regional hospital care capacity through cancellations of elective surgery and increased community care. Consequently, there were sustained system-wide hospital service improvements over the following weeks. CONCLUSIONS: The systematic collation of injured patient and healthcare system data has provided an objective evaluation of a regional major incident plan and provided insight into healthcare system resilience. Hospital patient care data indicated that a prerehearsed patient dispersal plan at incident scene was implemented effectively.

Traumatic brain injury probability of survival assessment in adults using iterative random comparison classification.

Trauma brain injury (TBI) is the most common cause of death and disability in young adults. A method to determine the probability of survival (Ps) in trauma called iterative random comparison classification (IRCC) was developed and its performance was evaluated in TBI. IRCC operates by iteratively comparing the test case with randomly chosen subgroups of cases from a database of known outcomes (survivors and not survivors) and determines the overall percentage match. The performance of IRCC to determine Ps in TBI was compared with two existing methods. One was Ps14 that uses regression and the other was predictive statistical diagnosis (PSD) that is based on Bayesian statistic. The TBI database contained 4124 adult cases (mean age 67.9 years, standard deviation 21.6) of which 3553 (86.2%) were survivors and 571 (13.8%) were not survivors. IRCC determined Ps for the survivors and not survivors with an accuracy of 79.0 and 71.4%, respectively, while the corresponding values for Ps14 were 97.4% (survivors) and 40.2% (not survivors) and for PSD were 90.8% (survivors) and 50% (not survivors). IRCC could be valuable for determining Ps in TBI and with a suitable database in other traumas.

Cost-effectiveness analysis of tranexamic acid for the treatment of traumatic brain injury, based on the results of the CRASH-3 randomised trial: a decision modelling approach.

INTRODUCTION: An estimated 69 million traumatic brain injuries (TBI) occur each year worldwide, with most in low-income and middle-income countries. The CRASH-3 randomised trial found that intravenous administration of tranexamic acid within 3 hours of injury reduces head injury deaths in patients sustaining a mild or moderate TBI. We examined the cost-effectiveness of tranexamic acid treatment for TBI. METHODS: A Markov decision model was developed to assess the cost-effectiveness of treatment with and without tranexamic acid, in addition to current practice. We modelled the decision in the UK and Pakistan from a health service perspective, over a lifetime time horizon. We used data from the CRASH-3 trial for the risk of death during the trial period (28 days) and patient quality of life, and data from the literature to estimate costs and long-term outcomes post-TBI. We present outcomes as quality-adjusted life years (QALYs) and 2018 costs in pounds for the UK, and US dollars for Pakistan. Incremental cost-effectiveness ratios (ICER) per QALY gained were estimated, and compared with country specific cost-effective thresholds. Deterministic and probabilistic sensitivity analyses were also performed. RESULTS: Tranexamic acid was highly cost-effective for patients with mild TBI and intracranial bleeding or patients with moderate TBI, at £4288 per QALY in the UK, and US$24 per QALY in Pakistan. Tranexamic acid was 99% and 98% cost-effective at the cost-effectiveness thresholds for the UK and Pakistan, respectively, and remained cost-effective across all deterministic sensitivity analyses. Tranexamic acid was even more cost-effective with earlier treatment administration. The cost-effectiveness for those with severe TBI was uncertain. CONCLUSION: Early administration of tranexamic acid is highly cost-effective for patients with mild or moderate TBI in the UK and Pakistan, relative to the cost-effectiveness thresholds used. The estimated ICERs suggest treatment is likely to be cost-effective across all income settings globally.

The effect of socioeconomic deprivation on 12 month Traumatic Brain Injury (TBI) outcome.

Objectives: To assess the impact of social deprivation on Traumatic Brain Injury (TBI) global outcome.Design: The study was a prospective observational study conducted using consecutive admissions with TBI.Subjects: 1322 consecutive adult patients with TBI were recruited into the study between 2010 and 2015.Methods: All patients were assessed by the TBI rehabilitation team at both six weeks and 12 months following TBI. Details of the injury and demographic data was collated at six weeks. This included age, gender and ZIP Code. Social deprivation was measured by the Indices of Multiple Deprivation (IMD) Score. The outcome measure used was the Extended Glasgow Outcome Score (GOSE) at 12 months. Univariate analysis was followed by a Multi-Ordinal Regression to evaluate predictor variables.Results: With regard to the representation of IMD deciles, the study population approximated to the general Sheffield population (p = .139). Within the univariate analysis, statistically significant relationships were noted between IMD and GOSE (p = <.001). The Ordinal Regression revealed a significant relationship between worse GOSE and IMD (p = .002), age (p = .001), GCS (p < .001), alcohol intoxication (p < .001) and Medical Comorbidity (p = .041).Conclusion: Increasing social deprivation is associated with poorer global TBI outcomes at 12 months.

Development of a Clinical Decision Rule for the Early Safe Discharge of Patients with Mild Traumatic Brain Injury and Findings on Computed Tomography Brain Scan: A Retrospective Cohort Study.

International guidelines recommend routine hospital admission for all patients with mild traumatic brain injury (TBI) who have injuries on computed tomography (CT) brain scan. Only a small proportion of these patients require neurosurgical or critical care intervention. We aimed to develop an accurate clinical decision rule to identify low-risk patients safe for discharge from the emergency department (ED) and facilitate earlier referral of those requiring intervention. A retrospective cohort study of case notes of patients admitted with initial Glasgow Coma Scale 13-15 and injuries identified by CT was completed. Data on a primary outcome measure of clinically important deterioration (indicating need for hospital admission) and secondary outcome of neurosurgery, intensive care unit admission, or intubation (indicating need for neurosurgical admission) were collected. Multi-variable logistic regression was used to derive models and a risk score predicting deterioration using routinely reported clinical and radiological candidate variables identified in a systematic review. We compared the performance of this new risk score with the Brain Injury Guideline (BIG) criteria, derived in the United States. A total of 1699 patients were included from three English major trauma centers. A total of 27.7% (95% confidence interval [CI], 25.5-29.9) met the primary and 13.1% (95% CI, 11.6-14.8) met the secondary outcomes of deterioration. The derived clinical decision rule suggests that patients with simple skull fractures or intracranial bleeding <5 mm in diameter who are fully conscious could be safely discharged from the ED. The decision rule achieved a sensitivity of 99.5% (95% CI, 98.1-99.9) and specificity of 7.4% (95% CI, 6.0-9.1) to the primary outcome. The BIG criteria achieved the same sensitivity, but lower specificity (5%). Our empirical models showed good predictive performance and outperformed the BIG criteria. This would potentially allow ED discharge of 1 in 20 patients currently admitted for observation. However, prospective external validation and economic evaluation are required.

Case-mix, care pathways, and outcomes in patients with traumatic brain injury in CENTER-TBI: a European prospective, multicentre, longitudinal, cohort study.

BACKGROUND: The burden of traumatic brain injury (TBI) poses a large public health and societal problem, but the characteristics of patients and their care pathways in Europe are poorly understood. We aimed to characterise patient case-mix, care pathways, and outcomes of TBI. METHODS: CENTER-TBI is a Europe-based, observational cohort study, consisting of a core study and a registry. Inclusion criteria for the core study were a clinical diagnosis of TBI, presentation fewer than 24 h after injury, and an indication for CT. Patients were differentiated by care pathway and assigned to the emergency room (ER) stratum (patients who were discharged from an emergency room), admission stratum (patients who were admitted to a hospital ward), or intensive care unit (ICU) stratum (patients who were admitted to the ICU). Neuroimages and biospecimens were stored in repositories and outcome was assessed at 6 months after injury. We used the IMPACT core model for estimating the expected mortality and proportion with unfavourable Glasgow Outcome Scale Extended (GOSE) outcomes in patients with moderate or severe TBI (Glasgow Coma Scale [GCS] score ≤12). The core study was registered with ClinicalTrials.gov, number NCT02210221, and with Resource Identification Portal (RRID: SCR_015582). FINDINGS: Data from 4509 patients from 18 countries, collected between Dec 9, 2014, and Dec 17, 2017, were analysed in the core study and from 22 782 patients in the registry. In the core study, 848 (19%) patients were in the ER stratum, 1523 (34%) in the admission stratum, and 2138 (47%) in the ICU stratum. In the ICU stratum, 720 (36%) patients had mild TBI (GCS score 13-15). Compared with the core cohort, the registry had a higher proportion of patients in the ER (9839 [43%]) and admission (8571 [38%]) strata, with more than 95% of patients classified as having mild TBI. Patients in the core study were older than those in previous studies (median age 50 years [IQR 30-66], 1254 [28%] aged >65 years), 462 (11%) had serious comorbidities, 772 (18%) were taking anticoagulant or antiplatelet medication, and alcohol was contributory in 1054 (25%) TBIs. MRI and blood biomarker measurement enhanced characterisation of injury severity and type. Substantial inter-country differences existed in care pathways and practice. Incomplete recovery at 6 months (GOSE <8) was found in 207 (30%) patients in the ER stratum, 665 (53%) in the admission stratum, and 1547 (84%) in the ICU stratum. Among patients with moderate-to-severe TBI in the ICU stratum, 623 (55%) patients had unfavourable outcome at 6 months (GOSE <5), similar to the proportion predicted by the IMPACT prognostic model (observed to expected ratio 1·06 [95% CI 0·97-1·14]), but mortality was lower than expected (0·70 [0·62-0·76]). INTERPRETATION: Patients with TBI who presented to European centres in the core study were older than were those in previous observational studies and often had comorbidities. Overall, most patients presented with mild TBI. The incomplete recovery of many patients should motivate precision medicine research and the identification of best practices to improve these outcomes. FUNDING: European Union 7th Framework Programme, the Hannelore Kohl Stiftung, OneMind, and Integra LifeSciences Corporation.

A multicentre randomised feasibility STUdy evaluating the impact of a prognostic model for Management of BLunt chest wall trauma patients: STUMBL Trial.

OBJECTIVE: A new prognostic model has been developed and externally validated, the aim of which is to assist in the management of the blunt chest wall trauma patient in the emergency department (ED). The aim of this trial is to assess the feasibility and acceptability of a definitive impact trial investigating the clinical and cost-effectiveness of a new prognostic model for the management of patients with blunt chest wall trauma in the ED. DESIGN: Stepped wedge feasibility trial. SETTING: Four EDs in England and Wales. PARTICIPANTS: Adult blunt chest wall trauma patients presenting to the ED with no concurrent, life-threatening injuries. INTERVENTION: A prognostic model (the STUMBL score) to guide clinical decision-making. OUTCOME MEASURES: Primary: participant recruitment rate and clinicians' use of the STUMBL score. Secondary: composite outcome measure (mortality, pulmonary complications, delayed upgrade in care, unplanned representations to the ED), physical and mental components of quality of life, clinician feedback and health economic data gathering methodology for healthcare resource utilisation. RESULTS: Quantitative data were analysed using the intention-to-treat principle. 176 patients were recruited; recruitment targets were achieved at all sites. Clinicians used the model in 96% of intervention cases. All feasibility criteria were fully or partially met. After adjusting for predefined covariates, there were no statistically significant differences between the control and intervention periods. Qualitative analysis highlighted that STUMBL was well-received and clinicians would support a definitive trial. Collecting data on intervention costs, health-related quality of life and healthcare resource use was feasible. DISCUSSION: We have demonstrated that a fully powered randomised clinical trial of the STUMBL score is feasible and desirable to clinicians. Minor methodological modifications will be made for the full trial. TRIAL REGISTRATION NUMBER: ISRCTN95571506; Post-results.

Selecting pregnant or postpartum women with suspected pulmonary embolism for diagnostic imaging: the DiPEP diagnostic study with decision-analysis modelling.

BACKGROUND: Pulmonary embolism (PE) is a leading cause of death in pregnancy and post partum, but the symptoms of PE are common in normal pregnancy. Simple diagnostic tests are needed to select women for diagnostic imaging. OBJECTIVE: To estimate the accuracy, effectiveness and cost-effectiveness of clinical features, decision rules and biomarkers for selecting pregnant or postpartum women with a suspected PE for imaging. DESIGN: An expert consensus study to develop new clinical decision rules, a case-control study of women with a diagnosed PE or a suspected PE, a biomarker study of women with a suspected PE or diagnosed deep-vein thrombosis (DVT) and decision-analysis modelling. SETTING: Emergency departments and consultant-led maternity units. PARTICIPANTS: Pregnant/postpartum women with a diagnosed PE from any hospital reporting to the UK Obstetric Surveillance System research platform and pregnant/postpartum women with a suspected PE or diagnosed DVT at 11 prospectively recruiting sites. INTERVENTIONS: Clinical features, decision rules and biomarkers. MAIN OUTCOME MEASURES: Sensitivity, specificity, area under receiver operating characteristic (AUROC) curve, quality-adjusted life-years (QALYs) and health-care costs. RESULTS: The primary analysis involved 181 women with PE and 259 women without PE in the case-control study and 18 women with DVT, 18 with PE and 247 women without either in the biomarker study. Most clinical features showed no association with PE. The AUROC curves for the clinical decision rules were as follows: primary consensus, 0.626; sensitive consensus, 0.620; specific consensus, 0.589; PE rule-out criteria, 0.621; simplified Geneva score, 0.579; Wells's PE criteria (permissive), 0.577; and Wells's PE criteria (strict), 0.732. The sensitivities and specificities of the D-dimer measurement were 88.4% and 8.8%, respectively, using a standard threshold, and 69.8% and 32.8%, respectively, using a pregnancy-specific threshold. Previous venous thromboembolism, long-haul travel, multiple pregnancy, oxygen saturation, recent surgery, temperature and PE-related chest radiograph abnormality were predictors of PE on multivariable analysis. We were unable to derive a rule through multivariable analysis or recursive partitioning with adequate accuracy. The AUROC curves for the biomarkers were as follows: activated partial thromboplastin time - 0.669, B-type natriuretic peptide - 0.549, C-reactive protein - 0.542, Clauss fibrinogen - 0.589, enzyme-linked immunosorbent assay D-dimer - 0.668, Innovance D-dimer (Siemens Healthcare Diagnostics Products GmbH, distributed by Sysmex UK Ltd, Milton Keynes, UK) - 0.651, mid-regional pro-atrial natriuretic peptide (MRproANP) - 0.524, prothrombin fragment 1 + 2 - 0.562, plasmin-antiplasmin - 0.639, Prothombin time - 0.613, thrombin generation lag time - 0.702, thrombin generation endogenous potential - 0.559, thrombin generation peak - 0.596, thrombin generation time to peak - 0.655, tissue factor - 0.531 and troponin - 0.597. The repeat analysis excluding women who had received anticoagulation was limited by the small number of women with PE (n = 4). The health economic analysis showed that a strategy of scanning all women with a suspected PE accrued more QALYs and incurred fewer costs than any selective strategy based on a clinical decision rule and was therefore the dominant strategy. LIMITATIONS: The findings apply specifically to the diagnostic assessment of women with a suspected PE in secondary care. CONCLUSIONS: Clinical features, decision rules and biomarkers do not accurately, effectively or cost-effectively select pregnant or postpartum women with a suspected PE for diagnostic imaging. FUTURE WORK: New diagnostic technologies need to be developed to detect PE in pregnancy. TRIAL REGISTRATION: Current Controlled Trials ISRCTN21245595. FUNDING DETAILS: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 47. See the NIHR Journals Library website for further project information.

Validating injury burden estimates using population birth cohorts and longitudinal cohort studies of injury outcomes: the VIBES-Junior study protocol.

INTRODUCTION: Traumatic injury is a leading contributor to the global disease burden in children and adolescents, but methods used to estimate burden do not account for differences in patterns of injury and recovery between children and adults. A lack of empirical data on postinjury disability in children has limited capacity to derive valid disability weights and describe the long-term individual and societal impacts of injury in the early part of life. The aim of this study is to establish valid estimates of the burden of non-fatal injury in children and adolescents. METHODS AND ANALYSIS: Five longitudinal studies of paediatric injury survivors <18 years at the time of injury (Australia, Canada, UK and USA) and two whole-of-population linked administrative data paediatric studies (Australia and Wales) will be analysed over a 3-year period commencing 2018. Meta-analysis of deidentified patient-level data (n≈2,600) from five injury-specific longitudinal studies (Victorian State Trauma Registry; Victorian Orthopaedic Trauma Outcomes Registry; UK Burden of Injury; British Columbia Children's Hospital Longitudinal Injury Outcomes; Children's Health After Injury) and >1 million children from two whole-of-population cohorts (South Australian Early Childhood Data Project and Wales Electronic Cohort for Children). Systematic analysis of pooled injury-specific cohort data using a variety of statistical techniques, and parallel analysis of whole-of-population cohorts, will be used to develop estimated disability weights for years lost due to disability, establish appropriate injury classifications and explore factors influencing recovery. ETHICS AND DISSEMINATION: The project was approved by the Monash University Human Research Ethics Committee project number 12 311. Results of this study will be submitted for publication in internationally peer-reviewed journals. The findings from this project have the capacity to improve the validity of paediatric injury burden measurements in future local and global burden of disease studies.

Protocol for a multicentre randomised feasibility STUdy evaluating the impact of a prognostic model for Management of BLunt chest wall trauma patients: STUMBL trial.

INTRODUCTION: A new prognostic model has been developed and externally validated, the aim of which is to assist in the management of the blunt chest wall trauma patient in the emergency department (ED). A definitive randomised controlled trial (impact trial) is required to assess the clinical and cost effectiveness of the new model before it can be accepted in clinical practice. The purpose of this trial is to assess the feasibility and acceptability of such a definitive trial and inform its design. METHODS/ANALYSIS: This feasibility trial is designed to test the methods of a multicentre, cluster-randomised (stepped- wedge) trial, with a substantial qualitative component. Four EDs in England and Wales will collect data for all blunt chest wall trauma patients over a 5-month period; in the initial period acting as the controls (normal care), and in the second period acting as the interventions (in which the new model will be used). Baseline measurements including completion of the SF-12v2 will be obtained on initial assessment in the ED. Patient outcome data will then be collected for any subsequent hospitalisations. Data collection will conclude with a 6-week follow-up completion of two surveys (SF-12v2 and Client Services Receipt Inventory). Analysis of outcomes will focus on feasibility, acceptability and trial processes and will include recruitment and retention rates, attendance at clinician training rates and use of model in the ED. Qualitative feedback will be obtained through clinician interviews and a research nurse focus group. An evaluation of the feasibility of health economics outcomes data will be completed. ETHICS AND DISSEMINATION: Wales Research Ethics Committee 6 granted approval for the trial in September 2016. Patient recruitment will commence in February 2017. Planned dissemination is through publication in a peer-reviewed Emergency Medicine Journal, presentation at appropriate conferences and to stakeholders at professional meetings. TRIAL REGISTRATION NUMBER: ISRCTN95571506; Pre-results.

Health State Preference Weights for the Glasgow Outcome Scale Following Traumatic Brain Injury: A Systematic Review and Mapping Study.

BACKGROUND: Valid and relevant estimates of health state preference weights (HSPWs) for Glasgow Outcome Scale (GOS) categories are a key input of economic models evaluating treatments for traumatic brain injury (TBI). OBJECTIVES: To characterize existing HSPW estimates, and model the EuroQol five-dimensional questionnaire (EQ-5D) from the GOS, to inform parameterization of future economic models. METHODS: A systematic review of HSPWs for GOS categories following TBI was conducted using a highly sensitive search strategy implemented in an extensive range of information sources between 1975 and 2016. A cross-sectional mapping study of GOS health states onto the three-level EQ-5D UK tariff index values was also performed in patients with significant TBI (head region Abbreviated Injury Scale score ≥3) from the Victoria State Trauma Registry. A limited dependent variable mixture model was used to estimate the 12-month EQ-5D UK value set as a function of GOS category, age, and other explanatory variables. RESULTS: Six unique HSPWs from five eligible studies were identified. All studies were at high risk of bias with limited applicability. The magnitude of HSPWs differed significantly between studies. Three class mixture models demonstrated excellent goodness of fit to the observed Victoria State Trauma Registry data. GOS category, age at injury, sex, comorbidity, and major extracranial injury all had significant independent effects on mean EQ-5D utility values. CONCLUSIONS: The few available HSPWs for GOS categories are challenged by potential biases and restricted generalizability. Mixture models are presented to provide HSPWs for GOS categories consistent with the National Institute for Health and Care Excellence reference case.