Diagnostic Accuracy of D-Dimer for Acute Aortic Syndromes: Systematic Review and Meta-Analysis.

STUDY OBJECTIVE: Acute aortic syndrome is a life-threatening emergency condition. Previous systematic reviews of D-dimer diagnostic accuracy for acute aortic syndrome have been contradictory and based on limited data, but recently published studies offer potential for a more definitive overview. We aimed to perform a systematic review and meta-analysis to determine the diagnostic accuracy of D-dimer for diagnosing acute aortic syndrome. METHODS: We searched MEDLINE, EMBASE, and the Cochrane Library from inception to February 2024. Additionally, the reference lists of included studies and other systematic reviews were thoroughly searched. All diagnostic cohort studies (prospective or retrospective) that assessed the use of D-dimer for diagnosing acute aortic syndrome compared with a reference standard test (eg, computed tomographic angiography (CTA), ECG-gated CTA, echocardiography, magnetic resonance angiography, operation, or autopsy) were included. Two independent reviewers completed study selection, data extractions and quality assessment using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. Data were synthesized using a bivariate meta-analysis model. RESULTS: Of 2017 potentially relevant citations, 25 cohort studies met the inclusion criteria, and 18 reporting the 500 ng/mL threshold were included in the primary meta-analysis. Risk of bias domains were mostly unclear due to limited study reporting. The summary sensitivity was 96.5% (95% credible interval [CrI] 94.8% to 98%) and summary specificity was 56.2% (95% CrI, 48.3% to 63.9%). Study specificity varied markedly from 33% to 86%, indicating substantial heterogeneity. Sensitivity analysis including the 7 studies reporting other thresholds showed summary sensitivity of 95.7% (95% CrI, 93.2% to 97.5%) and summary specificity of 57.5% (95% CrI, 50.1% to 64.6%). CONCLUSION: D-dimer concentration has high sensitivity (96.5%) and moderate specificity (56.2%) for acute aortic syndrome, with some uncertainty around estimates due to risk of bias and heterogeneity. Previous meta-analysis reporting higher specificity may be explained by inclusion of case-control studies that may overestimate accuracy.

Diagnostic accuracy of alternative biomarkers for acute aortic syndrome: a systematic review.

BACKGROUND: D-dimer is the only biomarker currently recommended in guidelines for the diagnosis of acute aortic syndrome (AAS). We undertook a systematic review to determine whether any alternative biomarkers could be useful in AAS diagnosis. METHODS: We searched electronic databases (including MEDLINE, EMBASE and the Cochrane Library) from inception to February 2024. Diagnostic studies were eligible if they examined biomarkers other than D-dimer for diagnosing AAS compared with a reference standard test in people presenting to the ED with symptoms of AAS. Case-control studies were identified but excluded due to high risk of bias. Selection of studies, data extraction and risk of bias assessments using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool were undertaken independently by at least two reviewers. We used narrative synthesis to summarise the findings. RESULTS: We identified 2017 citations, included 13 cohort studies (n=76-999), and excluded 38 case-control studies. Methodological quality was variable, with most included studies having unclear or high risk of bias and applicability concerns in at least one item of the QUADAS-2 tool. Only two studies reported biomarkers with sensitivity and specificity comparable to D-dimer (ie, >90% and >50%, respectively). Wang et al reported 99.1% sensitivity and 84.9% specificity for soluble ST2; however, these findings conflicted with estimates of 58% sensitivity and 70.8% specificity reported in another study. Chun and Siu reported 95.6% sensitivity and 56.1% specificity for neutrophil count, but this has not been confirmed elsewhere. CONCLUSION: There are many potential alternative biomarkers for AAS but few have been evaluated in more than one study, study designs are often weak and reported biomarker accuracy is modest or inconsistent between studies. Alternative biomarkers to D-dimer are not ready for routine clinical use. PROSPERO REGISTRATION NUMBER: CRD42022252121.

Thromboprophylaxis in lower limb immobilisation after injury (TiLLI).

Venous thromboembolic disease is a major global cause of morbidity and mortality. An estimated 10 million episodes are diagnosed yearly; over half of these episodes are provoked by hospital admission/procedures and result in significant loss of disability adjusted life years. Temporary lower limb immobilisation after injury is a significant contributor to the overall burden of venous thromboembolism (VTE). Existing evidence suggests that pharmacological prophylaxis could reduce overall VTE event rates in these patients, but the proportional reduction of symptomatic events remains unclear. Recent studies have used different pharmacological agents, dosing regimens and outcome measures. Consequently, there is wide variation in thromboprophylaxis strategies, and international guidelines continue to offer conflicting advice for clinicians. In this review, we provide a summary of recent evidence assessing both the clinical and cost effectiveness of thromboprophylaxis in patients with temporary immobilisation after injury. We also examine the evidence supporting stratified thromboprophylaxis and the validity of widely used risk assessment methods.

GENE EXPRESSION PROFILING AND EXPANDED IMMUNOHISTOCHEMISTRY TESTS TO GUIDE SELECTION OF CHEMOTHERAPY REGIMENS IN BREAST CANCER MANAGEMENT: A SYSTEMATIC REVIEW.

OBJECTIVES: The aim of this report was to assess the clinical effectiveness of two Gene expression profiling (GEP) and two expanded immunohistochemistry (IHC) tests compared with current prognostic tools in guiding the use of adjuvant chemotherapy in patients with early breast cancer. METHODS: A systematic review of the evidence on clinical effectiveness of OncotypeDX, IHC4, MammaPrint, and Mammostrat, compared with current clinical practice using clinicopathological parameters, in women with early breast cancer was conducted. Ten databases were searched to include citations to May 2016. RESULTS: Searches identified 7,064 citations, of which forty-one citations satisfied the criteria for the review. A narrative synthesis was performed. Evidence for OncotypeDX demonstrated the impact of the test on decision making and there was some support for OncotypeDX predicting chemotherapy benefit. There were relatively lower levels of evidence for the other three tests included in the analysis. MammaPrint, Mammostrat, and IHC4 tests were limited to a small number of studies. Limitations in relation to study design were identified for all tests. CONCLUSIONS: The evidence base for OncotypeDX is considered to be the most robust. Methodological weaknesses relating to heterogeneity of patient cohorts and issues arising from the retrospective nature of the evidence were identified. Further evidence is required for all of the tests using prospective randomized controlled trial data.

The use of rapid review methods in health technology assessments: 3 case studies.

BACKGROUND: Rapid reviews are of increasing importance within health technology assessment due to time and resource constraints. There are many rapid review methods available although there is little guidance as to the most suitable methods. We present three case studies employing differing methods to suit the evidence base for each review and outline some issues to consider when selecting an appropriate method. METHODS: Three recently completed systematic review short reports produced for the UK National Institute for Health Research were examined. Different approaches to rapid review methods were used in the three reports which were undertaken to inform the commissioning of services within the NHS and to inform future trial design. We describe the methods used, the reasoning behind the choice of methods and explore the strengths and weaknesses of each method. RESULTS: Rapid review methods were chosen to meet the needs of the review and each review had distinctly different challenges such as heterogeneity in terms of populations, interventions, comparators and outcome measures (PICO) and/or large numbers of relevant trials. All reviews included at least 10 randomised controlled trials (RCTs), each with numerous included outcomes. For the first case study (sexual health interventions), very diverse studies in terms of PICO were included. P-values and summary information only were presented due to substantial heterogeneity between studies and outcomes measured. For the second case study (premature ejaculation treatments), there were over 100 RCTs but also several existing systematic reviews. Data for meta-analyses were extracted directly from existing systematic reviews with new RCT data added where available. For the final case study (cannabis cessation therapies), studies included a wide range of interventions and considerable variation in study populations and outcomes. A brief summary of the key findings for each study was presented and narrative synthesis used to summarise results for each pair of interventions compared. CONCLUSIONS: Rapid review methods need to be chosen to meet both the nature of the evidence base of a review and the challenges presented by the included studies. Appropriate methods should be chosen after an assessment of the evidence base.

Sexual health risk reduction interventions for people with severe mental illness: a systematic review.

BACKGROUND: Despite variability in sexual activity among people with severe mental illness, high-risk sexual behavior (e.g. unprotected intercourse, multiple partners, sex trade and illicit drug use) is common. Sexual health risk reduction interventions (such as educational and behavioral interventions, motivational exercises, counselling and service delivery), developed and implemented for people with severe mental illness, may improve participants' knowledge, attitudes, beliefs behaviors or practices (including assertiveness skills) and could lead to a reduction in risky sexual behavior. This systematic review evaluates the effectiveness of sexual health risk reduction interventions for people with severe mental illness. METHODS: Thirteen electronic databases (including MEDLINE, EMBASE and PsycINFO) were searched to August 2014, and supplemented by hand-searching relevant articles and contacting experts. All controlled trials (randomized or non-randomized) comparing the effectiveness of sexual health risk reduction interventions with usual care for individuals living in the community with severe mental illness were included. Outcomes included a range of biological, behavioral and proxy endpoints. Narrative synthesis was used to combine the evidence. RESULTS: Thirteen controlled trials (all from the USA) were included. Although there was no clear and consistent evidence that interventions reduce the total number of sex partners or improved behavioral intentions in sexual risk behavior, positive effects were generally observed in condom use, condom protected intercourse and on measures of HIV knowledge, attitudes to condom use and sexual behaviors and practices. However, the robustness of these findings is low due to the large between study variability, small sample sizes and low-to-moderate quality of included studies. CONCLUSIONS: There is insufficient evidence at present to fully support or reject the identified sexual health risk reduction interventions for people with severe mental illness. Given the serious consequences of high-risk sexual behaviors, there is an urgent need for well-designed UK based trials, as well as training and support for staff implementing sexual health risk reduction interventions. TRIAL REGISTRATION: PROSPERO CRD42013003674 .

Diagnostic accuracy of the aortic dissection detection risk score alone or with D-dimer for acute aortic syndromes: Systematic review and meta-analysis.

OBJECTIVES: To evaluate the diagnostic accuracy of the aortic dissection detection risk score (ADD-RS) used alone or in combination with D-dimer for detecting acute aortic syndrome (AAS) in patients presenting with symptoms suggestive of AAS. METHODS: We searched MEDLINE, EMBASE, and the Cochrane Library from inception to February 2024. Additionally, the reference lists of included studies and other systematic reviews were thoroughly searched. All diagnostic accuracy studies that assessed the use of ADD-RS alone or with D-Dimer for diagnosing AAS compared with a reference standard test (e.g. computer tomographic angiography (CTA), ECG-gated CTA, echocardiography, magnetic resonance angiography, operation, or autopsy) were included. Two reviewers independently selected and extracted data. Risk of bias was appraised using QUADAS-2 tool. Data were synthesised using hierarchical meta-analysis models. RESULTS: We selected 13 studies from the 2017 citations identified, including six studies evaluating combinations of ADD-RS alongside D-dimer>500ng/L. Summary sensitivities and specificities (95% credible interval) were: ADD-RS>0 94.6% (90%, 97.5%) and 34.7% (20.7%, 51.2%), ADD-RS>1 43.4% (31.2%, 57.1%) and 89.3% (80.4%, 94.8%); ADD RS>0 or D-Dimer>500ng/L 99.8% (98.7%, 100%) and 21.8% (12.1%, 32.6%); ADD RS>1 or D-Dimer>500ng/L 98.3% (94.9%, 99.5%) and 51.4% (38.7%, 64.1%); ADD RS>1 or ADD RS = 1 with D-dimer>500ng/L 93.1% (87.1%, 96.3%) and 67.1% (54.4%, 77.7%). CONCLUSIONS: Combinations of ADD-RS and D-dimer can be used to select patients with suspected AAS for imaging with a range of trade-offs between sensitivity (93.1% to 99.8%) and specificity (21.8% to 67.1%).

Thromboprophylaxis during pregnancy and the puerperium: a systematic review and economic evaluation to estimate the value of future research.

Background: Pharmacological prophylaxis to prevent venous thromboembolism is currently recommended for women assessed as being at high risk of venous thromboembolism during pregnancy or in the 6 weeks after delivery (the puerperium). The decision to provide thromboprophylaxis involves weighing the benefits, harms and costs, which vary according to the individual's venous thromboembolism risk. It is unclear whether the United Kingdom's current risk stratification approach could be improved by further research. Objectives: To quantify the current decision uncertainty associated with selecting women who are pregnant or in the puerperium for thromboprophylaxis and to estimate the value of one or more potential future studies that would reduce that uncertainty, while being feasible and acceptable to patients and clinicians. Methods: A decision-analytic model was developed which was informed by a systematic review of risk assessment models to predict venous thromboembolism in women who are pregnant or in the puerperium. Expected value of perfect information analysis was used to determine which factors are associated with high decision uncertainty and should be the target of future research. To find out whether future studies would be acceptable and feasible, we held workshops with women who have experienced a blood clot or have been offered blood-thinning drugs and surveyed healthcare professionals. Expected value of sample information analysis was used to estimate the value of potential future research studies. Results: The systematic review included 17 studies, comprising 19 unique externally validated risk assessment models and 1 internally validated model. Estimates of sensitivity and specificity were highly variable ranging from 0% to 100% and 5% to 100%, respectively. Most studies had unclear or high risk of bias and applicability concerns. The decision analysis found that there is substantial decision uncertainty regarding the use of risk assessment models to select high-risk women for antepartum prophylaxis and obese postpartum women for postpartum prophylaxis. The main source of decision uncertainty was uncertainty around the effectiveness of thromboprophylaxis for preventing venous thromboembolism in women who are pregnant or in the puerperium. We found that a randomised controlled trial of thromboprophylaxis in obese postpartum women is likely to have substantial value and is more likely to be acceptable and feasible than a trial recruiting women who have had a previous venous thromboembolism. In unselected postpartum women and women following caesarean section, the poor performance of risk assessment models meant that offering prophylaxis based on these models had less favourable cost effectiveness with lower decision uncertainty. Limitations: The performance of the risk assessment model for obese postpartum women has not been externally validated. Conclusions: Future research should focus on estimating the efficacy of pharmacological thromboprophylaxis in pregnancy and the puerperium, and clinical trials would be more acceptable in women who have not had a previous venous thromboembolism. Study registration: This study is registered as PROSPERO CRD42020221094. Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: NIHR131021) and is published in full in Health Technology Assessment; Vol. 28, No. 9. See the NIHR Funding and Awards website for further award information.

Women who are pregnant or who have given birth in the previous 6 weeks are at increased risk of developing blood clots that can cause serious illness or death. Small doses of blood thinners given by injection are safe in pregnancy and can reduce the risk of blood clots, but they can slightly increase the risk of bleeding. Healthcare professionals use risk assessment tools to decide if a woman is at high risk of blood clots and should be offered blood thinners. We wanted to find out what research would be useful to help them make better decisions. We reviewed previous research to establish which risk assessment tools are best at predicting who will have a blood clot. We then created a mathematical model to predict what would happen when using different risk assessment tools to decide who should be offered blood thinners, both during pregnancy and after giving birth. We found that there was a lot of uncertainty about which women should be offered blood thinners. This was mainly because there have only been a few small studies comparing blood thinners to no treatment in pregnant women or women who have recently given birth. We estimated the value of future studies comparing blood thinners to no treatment, in groups of women with different risk factors, by predicting what information we would gain and how this would be used to improve decisions about using blood thinners. To find out whether these studies would be acceptable and feasible, we held workshops with women who have experienced a blood clot or have been offered blood thinners and surveyed healthcare professionals. We found that a study in obese women who have recently given birth would have substantial value and may be more acceptable than a study in pregnant women with a previous blood clot.

Effectiveness and cost effectiveness of pharmacological thromboprophylaxis for medical inpatients: decision analysis modelling study.

Objective: To determine the balance of costs, risks, and benefits for different thromboprophylaxis strategies for medical patients during hospital admission. Design: Decision analysis modelling study. Setting: NHS hospitals in England. Population: Eligible adult medical inpatients, excluding patients in critical care and pregnant women. Interventions: Pharmacological thromboprophylaxis (low molecular weight heparin) for all medical inpatients, thromboprophylaxis for none, and thromboprophylaxis given to higher risk inpatients according to risk assessment models (Padua, Caprini, IMPROVE, Intermountain, Kucher, Geneva, and Rothberg) previously validated in medical cohorts. Main outcome measures: Lifetime costs and quality adjusted life years (QALYs). Costs were assessed from the perspective of the NHS and Personal Social Services in England. Other outcomes assessed were incidence and treatment of venous thromboembolism, major bleeds including intracranial haemorrhage, chronic thromboembolic complications, and overall survival. Results: Offering thromboprophylaxis to all medical inpatients had a high probability (>99%) of being the most cost effective strategy (at a threshold of £20 000 (€23 440; $25 270) per QALY) in the probabilistic sensitivity analysis, when applying performance data from the Padua risk assessment model, which was typical of that observed across several risk assessment models in a medical inpatient cohort. Thromboprophylaxis for all medical inpatients was estimated to result in 0.0552 additional QALYs (95% credible interval 0.0209 to 0.1111) while generating cost savings of £28.44 (-£47 to £105) compared with thromboprophylaxis for none. No other risk assessment model was more cost effective than thromboprophylaxis for all medical inpatients when assessed in deterministic analysis. Risk based thromboprophylaxis was found to have a high (76.6%) probability of being the most cost effective strategy only when assuming a risk assessment model with very high sensitivity is available (sensitivity 99.9% and specificity 23.7% v base case sensitivity 49.3% and specificity 73.0%). Conclusions: Offering pharmacological thromboprophylaxis to all eligible medical inpatients appears to be the most cost effective strategy. To be cost effective, any risk assessment model would need to have a very high sensitivity resulting in widespread thromboprophylaxis in all patients except those at the very lowest risk, who could potentially avoid prophylactic anticoagulation during their hospital stay.

Estimating the value of future research into thromboprophylaxis for women during pregnancy and after delivery: a value of information analysis.

BACKGROUND: Risk assessment models (RAMs) are used to select women at increased risk of venous thromboembolism (VTE) during pregnancy and the puerperium for thromboprophylaxis. OBJECTIVES: To estimate the value of potential future studies that would reduce the decision uncertainty associated with offering thromboprophylaxis according to available RAMs in the following groups: high-risk antepartum women (eg, prior VTE), unselected postpartum women, and postpartum women with risk factors (obesity or cesarean delivery). METHODS: A decision-analytic model was developed to simulate clinical outcomes, lifetime costs, and quality-adjusted life-years for different thromboprophylaxis strategies, including thromboprophylaxis for all, thromboprophylaxis for none, and RAM-based thromboprophylaxis. The expected value of perfect information analysis was used to determine which factors are associated with high decision uncertainty. The value of future research studies was estimated using expected value of sample information analysis. Costs were assessed from a health and social services perspective. RESULTS: The expected value of perfect information analysis identified high decision uncertainty for high-risk antepartum women (£21.8 million) and obese postpartum women (£13.4 million), which was largely attributable to uncertainty regarding the effectiveness of thromboprophylaxis in reducing VTE. A randomized controlled trial of thromboprophylaxis compared with none in obese postpartum women is likely to have substantial value (£2.8 million; 300 participants per arm). A trial in women with previous VTE would have higher value but would be less acceptable. CONCLUSION: Future research should focus on estimating the effectiveness of thromboprophylaxis in obese postpartum women with additional risk factors who have not had a previous VTE.

Evaluation of venous thromboembolism risk assessment models for hospital inpatients: the VTEAM evidence synthesis.

Background: Pharmacological prophylaxis during hospital admission can reduce the risk of acquired blood clots (venous thromboembolism) but may cause complications, such as bleeding. Using a risk assessment model to predict the risk of blood clots could facilitate selection of patients for prophylaxis and optimise the balance of benefits, risks and costs. Objectives: We aimed to identify validated risk assessment models and estimate their prognostic accuracy, evaluate the cost-effectiveness of different strategies for selecting hospitalised patients for prophylaxis, assess the feasibility of using efficient research methods and estimate key parameters for future research. Design: We undertook a systematic review, decision-analytic modelling and observational cohort study conducted in accordance with Enhancing the QUAlity and Transparency Of health Research (EQUATOR) guidelines. Setting: NHS hospitals, with primary data collection at four sites. Participants: Medical and surgical hospital inpatients, excluding paediatric, critical care and pregnancy-related admissions. Interventions: Prophylaxis for all patients, none and according to selected risk assessment models. Main outcome measures: Model accuracy for predicting blood clots, lifetime costs and quality-adjusted life-years associated with alternative strategies, accuracy of efficient methods for identifying key outcomes and proportion of inpatients recommended prophylaxis using different models. Results: We identified 24 validated risk assessment models, but low-quality heterogeneous data suggested weak accuracy for prediction of blood clots and generally high risk of bias in all studies. Decision-analytic modelling showed that pharmacological prophylaxis for all eligible is generally more cost-effective than model-based strategies for both medical and surgical inpatients, when valuing a quality-adjusted life-year at £20,000. The findings were more sensitive to uncertainties in the surgical population; strategies using risk assessment models were more cost-effective if the model was assumed to have a very high sensitivity, or the long-term risks of post-thrombotic complications were lower. Efficient methods using routine data did not accurately identify blood clots or bleeding events and several pre-specified feasibility criteria were not met. Theoretical prophylaxis rates across an inpatient cohort based on existing risk assessment models ranged from 13% to 91%. Limitations: Existing studies may underestimate the accuracy of risk assessment models, leading to underestimation of their cost-effectiveness. The cost-effectiveness findings do not apply to patients with an increased risk of bleeding. Mechanical thromboprophylaxis options were excluded from the modelling. Primary data collection was predominately retrospective, risking case ascertainment bias. Conclusions: Thromboprophylaxis for all patients appears to be generally more cost-effective than using a risk assessment model, in hospitalised patients at low risk of bleeding. To be cost-effective, any risk assessment model would need to be highly sensitive. Current evidence on risk assessment models is at high risk of bias and our findings should be interpreted in this context. We were unable to demonstrate the feasibility of using efficient methods to accurately detect relevant outcomes for future research. Future work: Further research should evaluate routine prophylaxis strategies for all eligible hospitalised patients. Models that could accurately identify individuals at very low risk of blood clots (who could discontinue prophylaxis) warrant further evaluation. Study registration: This study is registered as PROSPERO CRD42020165778 and Researchregistry5216. Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: NIHR127454) and will be published in full in Health Technology Assessment; Vol. 28, No. 20. See the NIHR Funding and Awards website for further award information.

People who are admitted to hospital are at risk of blood clots that can cause serious illness or death. Patients are often given low doses of blood-thinning drugs to reduce this risk. However, these drugs can cause side effects, such as bleeding. Hospitals currently use complex risk assessment models (risk scores, which usually include patient, disease, mobility and intervention factors) to determine the individual risk of blood clots and identify people most likely to benefit from blood-thinning drugs. There are a lot of different risk scores and we do not know which one is best. We also do not know how these scores compare to each other or whether using scores to decide who should get blood-thinning drugs provides good value for money to the NHS. We reviewed all previous studies of risk scores. We found that they did not predict blood clots very well and we could not recommend one score over another. We then created a mathematical model to simulate the use of blood-thinning drugs in people admitted to hospital. The model suggested that giving blood-thinning drugs to everyone who could have them would probably provide the best value for money, in medical patients. Our findings were the same, but less certain, for surgical patients. We also collected information from four NHS hospitals to explore possibilities for future research. Our work showed that routinely collected electronic data on blood clots and bleeding events is not very accurate and that using different scores could result in variable use of blood-thinning medications. Our findings suggest that it may be better value to the NHS and better for patients if we were to offer blood-thinning medications to everyone on admission to hospital, without using any risk score. However, this approach needs further research to ensure it is safe and effective. Such research would not be able to rely on routine electronic data to identify blood clots or bleeding events, in isolation.

Cervical spine immobilisation following blunt trauma in pre-hospital and emergency care: A systematic review.

OBJECTIVES: To assess whether different cervical spine immobilisation strategies (full immobilisation, movement minimisation or no immobilisation), impact neurological and/or other outcomes for patients with suspected cervical spinal injury in the pre-hospital and emergency department setting. DESIGN: Systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. DATA SOURCES: MEDLINE, EMBASE, CINAHL, Cochrane Library and two research registers were searched until September 2023. ELIGIBILITY CRITERIA: All comparative studies (prospective or retrospective) that examined the potential benefits and/or harms of immobilisation practices during pre-hospital and emergency care of patients with a potential cervical spine injury (pre-imaging) following blunt trauma. DATA EXTRACTION AND SYNTHESIS: Two authors independently selected and extracted data. Risk of bias was appraised using the Cochrane ROBINS-I tool for non-randomised studies. Data were synthesised without meta-analysis. RESULTS: Six observational studies met the inclusion criteria. The methodological quality was variable, with most studies having serious or critical risk of bias. The effect of cervical spine immobilisation practices such as full immobilisation or movement minimisation during pre-hospital and emergency care did not show clear evidence of benefit for the prevention of neurological deterioration, spinal injuries and death compared with no immobilisation. However, increased pain, discomfort and anatomical complications were associated with collar application during immobilisation. CONCLUSIONS: Despite the limited evidence, weak designs and limited generalisability, the available data suggest that pre-hospital cervical spine immobilisation (full immobilisation or movement minimisation) was of uncertain value due to the lack of demonstrable benefit and may lead to potential complications and adverse outcomes. High-quality randomised comparative studies are required to address this important question. TRIAL REGISTRATION: PROSPERO REGISTRATION Fiona Lecky, Abdullah Pandor, Munira Essat, Anthea Sutton, Carl Marincowitz, Gordon Fuller, Stuart Reid, Jason Smith. A systematic review of cervical spine immobilisation following blunt trauma in pre-hospital and emergency care. PROSPERO 2022 CRD42022349600 Available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022349600.

Cost-effectiveness of therapeutics for COVID-19 patients: a rapid review and economic analysis.

Background: Severe acute respiratory syndrome coronavirus 2 is the virus that causes coronavirus disease 2019. Over six million deaths worldwide have been associated with coronavirus disease 2019. Objective: To assess the cost-effectiveness of treatments used for the treatment of coronavirus disease 2019 in hospital or used in the community in patients with coronavirus disease 2019 at high risk of hospitalisation. Setting: Treatments provided in United Kingdom hospital and community settings. Methods: Clinical effectiveness estimates were taken from the coronavirus disease-network meta-analyses initiative and the metaEvidence initiative. A mathematical model was constructed to explore how the interventions impacted on patient health, measured in quality-adjusted life-years gained. The costs associated with treatment, including those of hospital care, were also estimated and used to form a cost per quality-adjusted life-year gained value which was compared with thresholds published by the National Institute for Health and Care Excellence. Estimates of cost-effectiveness compared against current standard of care were produced in both the hospital and community settings at three different levels of efficacy: mean, low and high. Public list prices were used for interventions with neither confidential patient access schemes nor confidential list prices considered. Results incorporating confidential pricing data were provided to the National Institute for Health and Care Excellence appraisal committee. Results: The treatments were estimated to be clinically effective although not all reached statistical significance. All treatments in the hospital setting, or community, were estimated to plausibly have a cost per quality-adjusted life-year gained value below National Institute for Health and Care Excellence's thresholds when compared with standard of care. However, almost all drugs could plausibly have cost per quality-adjusted life-years above National Institute for Health and Care Excellence's thresholds. However, there is considerable uncertainty in the results as the prevalent severe acute respiratory syndrome coronavirus 2 variant, vaccination status, history of being infected with severe acute respiratory syndrome coronavirus 2 and standard of care have all evolved since the pivotal studies were conducted which could have significant impact on the efficacy of each drug. For drugs used in high-risk patients in the community setting, the proportion of people at high risk who need hospital admission was a large driver of the cost per quality-adjusted life-year. Limitations: No studies were identified that were conducted in current conditions. This may be a large limitation as the severe acute respiratory syndrome coronavirus 2 variant changes. No head-to-head studies of interventions were identified. Conclusions: The results produced could be informative to decision-makers, although conclusions regarding the most clinical - and cost-effectiveness of each intervention should be tentative due to the evolving nature of the decision problem and, in this report, the use of list prices only. Comparisons between interventions should also be treated with caution due to potentially large heterogeneity between studies. Future work: Research assessing the relative clinical effectiveness of interventions within head-to-head studies in current conditions would be beneficial. Contemporary information related to the probability of hospital admission and death for patients at high risk in the community would improve the precision of the estimates generated. Funding: This project was funded by the National Institute for Health and Care Research (NIHR) Evidence Synthesis programme (NIHR135564) and will be published in full in Health Technology Assessment; Vol. 27, No. 14. See the NIHR Journals Library website for further project information.

Coronavirus disease 2019 is an infectious disease that can cause death and long-term ill-health. Treatments exist that can be provided in hospital to reduce the number of deaths from coronavirus disease 2019. Treatments also exist which can be provided in the community for people at high risk of needing to be admitted to hospital to reduce the number of admissions and to reduce the number of deaths from coronavirus disease 2019. However, the value for money of these treatments has not been estimated. We took the clinical effectiveness of nine treatments from published literature sources and built a model that estimated the value for money of six treatments compared with care without these treatments. Three treatments were excluded due to confidential prices. The results of the model showed that many treatments in a hospital setting had estimates of cost-effectiveness that would normally be seen to be good value for money using the thresholds published by the National Institute of Health and Care Excellence. The same was true for some treatments in a community setting. However, it is also possible that these treatments are not good value for money. The benefit of the drugs and value for money is highly uncertain as studies trying to estimate the gain have been done with (1) previous variants of the virus causing coronavirus disease 2019 being widespread, (2) where the proportion of people who have had vaccinations or who had previously had coronavirus disease 2019 is low and (3) where standard treatment was that when coronavirus disease 2019 was first identified, and not the drugs used now. Because of these differences, and the unknown price of some interventions, we cannot confidently say which (if any) treatments help patients the most, or which treatment represents the best value for money. Further research, in current conditions, would improve the accuracy of our answers.

Decision-analysis modeling of effectiveness and cost-effectiveness of pharmacologic thromboprophylaxis for surgical inpatients using variable risk assessment models or other strategies.

BACKGROUND: Surgical inpatients are at a risk of venous thromboembolism (VTE), which can be life-threatening or result in chronic complications. Thromboprophylaxis reduces the VTE risk but incurs costs and may increase bleeding risk. Risk assessment models (RAMs) are currently used to target thromboprophylaxis at high-risk patients. OBJECTIVES: To determine the balance of cost, risk, and benefit for different thromboprophylaxis strategies in adult surgical inpatients, excluding patients who underwent major orthopedic surgery or were under critical care and pregnant women. METHODS: Decision analytic modeling was performed to estimate the following outcomes for alternative thromboprophylaxis strategies: thromboprophylaxis usage; VTE incidence and treatment; major bleeding; chronic thromboembolic complications; and overall survival. Strategies compared were as follows: no thromboprophylaxis; thromboprophylaxis for all; and thromboprophylaxis given according to RAMs (Caprini and Pannucci). Thromboprophylaxis is assumed to be given for the duration of hospitalization. The model evaluates lifetime costs and quality-adjusted life-years (QALYs) within England's health and social care services. RESULTS: Thromboprophylaxis for all surgical inpatients had a 70% probability of being the most cost-effective strategy (at a £20 000 per QALY threshold). RAM-based prophylaxis would be the most cost-effective strategy if a RAM with a higher sensitivity (99.9%) were available for surgical inpatients. QALY gains were mainly due to reduced postthrombotic complications. The optimal strategy was sensitive to several other factors such as the risk of VTE, bleeding and postthrombotic syndrome, duration of prophylaxis, and patient age. CONCLUSION: Thromboprophylaxis for all eligible surgical inpatients seemed to be the most cost-effective strategy. Default recommendations for pharmacologic thromboprophylaxis, with the potential to opt-out, may be superior to a complex risk-based opt-in approach.

Individual risk factors predictive of major trauma in pre-hospital injured older patients: a systematic review.

Background: Older adults with major trauma are frequently under-triaged, increasing the risk of preventable morbidity and mortality. The aim of this systematic review was to identify which individual risk factors and predictors are likely to increase the risk of major trauma in elderly patients presenting to emergency medical services (EMS) following injury, to inform future elderly triage tool development. Methods: Several electronic databases (including Medline, EMBASE, CINAHL and the Cochrane Library) were searched from inception to February 2021. Prospective or retrospective diagnostic studies were eligible if they examined a prognostic factor (often termed predictor or risk factor) for, or diagnostic test to identify, major trauma. Selection of studies, data extraction and risk of bias assessments using the Quality in Prognostic Studies (QUIPS) tool were undertaken independently by at least two reviewers. Narrative synthesis was used to summarise the findings. Results: Nine studies, all performed in US trauma networks, met review inclusion criteria. Vital signs (Glasgow Coma Scale (GCS) score, systolic blood pressure, respiratory rate and shock index with specific elderly cut-off points), EMS provider judgement, comorbidities and certain crash scene variables (other occupants injured, occupant not independently mobile and head-on collision) were identified as significant pre-hospital variables associated with major trauma in the elderly in multi-variable analyses. Heart rate and anticoagulant were not significant predictors. Included studies were at moderate or high risk of bias, with applicability concerns secondary to selected study populations. Conclusions: Existing pre-hospital major trauma triage tools could be optimised for elderly patients by including elderly-specific physiology thresholds. Future work should focus on more relevant reference standards and further evaluation of novel elderly relevant triage tool variables and thresholds.

Risk assessment models for venous thromboembolism in pregnancy and in the puerperium: a systematic review.

OBJECTIVES: To assess the comparative accuracy of risk assessment models (RAMs) to identify women during pregnancy and the early postnatal period who are at increased risk of venous thromboembolism (VTE). DESIGN: Systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. DATA SOURCES: MEDLINE, Embase, Cochrane Library and two research registers were searched until February 2021. ELIGIBILITY CRITERIA: All validation studies that examined the accuracy of a multivariable RAM (or scoring system) for predicting the risk of developing VTE in women who are pregnant or in the puerperium (within 6 weeks post-delivery). DATA EXTRACTION AND SYNTHESIS: Two authors independently selected and extracted data. Risk of bias was appraised using PROBAST (Prediction model Risk Of Bias ASsessment Tool). Data were synthesised without meta-analysis. RESULTS: Seventeen studies, comprising 19 externally validated RAMs and 1 internally validated model, met the inclusion criteria. The most widely evaluated RAMs were the Royal College of Obstetricians and Gynaecologists guidelines (six studies), American College of Obstetricians and Gynecologists guidelines (two studies), Swedish Society of Obstetrics and Gynecology guidelines (two studies) and the Lyon score (two studies). In general, estimates of sensitivity and specificity were highly variable with sensitivity estimates ranging from 0% to 100% for RAMs that were applied to antepartum women to predict antepartum or postpartum VTE and 0% to 100% for RAMs applied postpartum to predict postpartum VTE. Specificity estimates were similarly diverse ranging from 28% to 98% and 5% to 100%, respectively. CONCLUSIONS: Available data suggest that external validation studies have weak designs and limited generalisability, so estimates of prognostic accuracy are very uncertain. PROSPERO REGISTRATION NUMBER: CRD42020221094.

Clinical decision rules for adults with minor head injury: a systematic review.

BACKGROUND: There are many clinical decision rules for adults with minor head injury, but it is unclear how they compare in terms of diagnostic accuracy. This study aimed to systematically identify clinical decision rules for adults with minor head injury and compare the estimated diagnostic accuracies for any intracranial injury and injury requiring neurosurgical intervention. METHODS: Several electronic bibliographic databases covering biomedical, scientific, and gray literature were searched from inception to March 2010. At least two independent reviewers determined the eligibility of cohort studies that described a clinical decision rule to identify adults with minor head injury (Glasgow Coma Scale score, 13-15) at risk of intracranial injury or injury requiring neurosurgical intervention. RESULTS: Twenty-two relevant studies were identified. Differences existed in patient selection, outcome definition, and reference standards used. Nine rules stratified patients into high- and moderate-risk categories (to identify neurosurgical or nonsurgical intracranial lesions). The Canadian Computed Tomography Head Rule (CCHR) high-risk criteria have sensitivity of 99% to 100% with specificity of 48% to 77% for injury requiring neurosurgical intervention. Other rules such as New Orleans criteria, National Emergency X-Radiography Utilization Study II, Neurotraumatology Committee of the World Federation of Neurosurgical Societies, Scandinavian, and Scottish Intercollegiate Guidelines Network produce similar sensitivities for injury requiring neurosurgical intervention but with lower and more variable specificity values. DISCUSSION: The most widely researched decision rule is the CCHR, which has consistently shown high sensitivity for identifying injury requiring neurosurgical intervention with an acceptable specificity to allow considered use of cranial computed tomography. No other decision rule has been as widely validated or demonstrated as acceptable results, but its exclusion criteria make it difficult to apply universally.

Diagnostic accuracy of prehospital triage tools for identifying major trauma in elderly injured patients: A systematic review.

BACKGROUND: Older adults with major trauma are frequently undertriaged, increasing the risk of preventable morbidity and mortality. The aim of this systematic review was to evaluate the diagnostic performance of prehospital triage tools to identify suspected elderly trauma patients in need of specialized trauma care. METHODS: Several electronic databases (including MEDLINE, EMBASE, and the Cochrane Library) were searched from inception to February 2019. Prospective or retrospective diagnostic studies were eligible if they examined prehospital triage tools as index tests (either scored theoretically using observed patient variables or evaluated according to actual paramedic transport decisions) compared with a reference standard for major trauma in elderly adults who require transport by paramedics following injury. Selection of studies, data extraction, and risk of bias assessments using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool were undertaken independently by at least two reviewers. Narrative synthesis was used to summarize the findings. RESULTS: Fifteen studies met the inclusion criteria, with 11 studies examining theoretical accuracy, three evaluating real-life transport decisions, and one assessing both (of 21 individual index tests). Estimates for sensitivity and specificity were highly variable with sensitivity estimates ranging from 19.8% to 95.5% and 57.7% to 83.3% for theoretical accuracy and real life triage performance, respectively. Specificity results were similarly diverse ranging from 17.0% to 93.1% for theoretical accuracy and 46.3% to 78.9% for actual paramedic decisions. Most studies had unclear or high risk of bias and applicability concerns. There were no obvious differences between different triage tools, and findings did not appear to vary systematically with major trauma prevalence, age, alternative reference standards, study designs, or setting. CONCLUSION: Existing prehospital triage tools may not accurately identify elderly patients with serious injury. Future work should focus on more relevant reference standards, establishing the best trade-off between undertriage and overtriage, optimizing the role prehospital clinician judgment, and further developing geriatric specific triage variables and thresholds. LEVEL OF EVIDENCE: Systematic review, level III.

Risk assessment models for venous thromboembolism in hospitalised adult patients: a systematic review.

INTRODUCTION: Hospital-acquired thrombosis accounts for a large proportion of all venous thromboembolism (VTE), with significant morbidity and mortality. This subset of VTE can be reduced through accurate risk assessment and tailored pharmacological thromboprophylaxis. This systematic review aimed to determine the comparative accuracy of risk assessment models (RAMs) for predicting VTE in patients admitted to hospital. METHODS: A systematic search was performed across five electronic databases (including MEDLINE, EMBASE and the Cochrane Library) from inception to February 2021. All primary validation studies were eligible if they examined the accuracy of a multivariable RAM (or scoring system) for predicting the risk of developing VTE in hospitalised inpatients. Two or more reviewers independently undertook study selection, data extraction and risk of bias assessments using the PROBAST (Prediction model Risk Of Bias ASsessment Tool) tool. We used narrative synthesis to summarise the findings. RESULTS: Among 6355 records, we included 51 studies, comprising 24 unique validated RAMs. The majority of studies included hospital inpatients who required medical care (21 studies), were undergoing surgery (15 studies) or receiving care for trauma (4 studies). The most widely evaluated RAMs were the Caprini RAM (22 studies), Padua prediction score (16 studies), IMPROVE models (8 studies), the Geneva risk score (4 studies) and the Kucher score (4 studies). C-statistics varied markedly between studies and between models, with no one RAM performing obviously better than other models. Across all models, C-statistics were often weak (<0.7), sometimes good (0.7-0.8) and a few were excellent (>0.8). Similarly, estimates for sensitivity and specificity were highly variable. Sensitivity estimates ranged from 12.0% to 100% and specificity estimates ranged from 7.2% to 100%. CONCLUSION: Available data suggest that RAMs have generally weak predictive accuracy for VTE. There is insufficient evidence and too much heterogeneity to recommend the use of any particular RAM. PROSPERO REGISTRATION NUMBER: Steve Goodacre, Abdullah Pandor, Katie Sworn, Daniel Horner, Mark Clowes. A systematic review of venous thromboembolism RAMs for hospital inpatients. PROSPERO 2020 CRD42020165778. Available from https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=165778https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=165778.