Role of inflammatory markers in the assessment of meningitis in adult patients with fever and headache.

BACKGROUND: Meningitis, especially of bacterial origin, is a medical emergency that must be diagnosed promptly. However, due to the associated risks of complications of lumbar puncture, it is crucial to identify individuals who truly need it. The aim of this study was to assess the diagnostic role of inflammatory markers in distinguishing among patients without meningitis, those with aseptic meningitis, and those with bacterial meningitis. METHODS: This was a retrospective, diagnostic study at an acute care hospital, involving adult patients who presented to either ambulatory care or the emergency department with fever and headache, but without altered mental status or neurological deficits. Inflammatory markers (C-reactive protein [CRP], mean platelet volume, neutrophil-lymphocyte ratio, and red cell distribution width) were assessed as index tests. An expert panel classified patients into three groups: no meningitis, aseptic meningitis, and bacterial meningitis using predefined criteria. RESULTS: Of the 80 patients, 52 had no meningitis, 27 had aseptic meningitis, and 1 had bacterial meningitis. Of the inflammatory markers investigated, only CRP showed potential usefulness in differentiating these three diagnostic groups, with median values of 5.6 (interquartile range [IQR] 2.1, 11.3) mg/dL in those without meningitis, 0.2 (IQR 0.1, 1.2) mg/dL in those with aseptic meningitis, and notably elevated at 21.7 mg/dL in the patient with bacterial meningitis. CONCLUSION: In adult patients presenting with fever and headache in an emergency setting, CRP was the only marker that demonstrated potential diagnostic utility in distinguishing among those with no meningitis, aseptic meningitis, and bacterial meningitis.

Diagnostic management of acute pulmonary embolism: a prediction model based on a patient data meta-analysis.

AIMS: Risk stratification is used for decisions regarding need for imaging in patients with clinically suspected acute pulmonary embolism (PE). The aim was to develop a clinical prediction model that provides an individualized, accurate probability estimate for the presence of acute PE in patients with suspected disease based on readily available clinical items and D-dimer concentrations. METHODS AND RESULTS: An individual patient data meta-analysis was performed based on sixteen cross-sectional or prospective studies with data from 28 305 adult patients with clinically suspected PE from various clinical settings, including primary care, emergency care, hospitalized and nursing home patients. A multilevel logistic regression model was built and validated including ten a priori defined objective candidate predictors to predict objectively confirmed PE at baseline or venous thromboembolism (VTE) during follow-up of 30 to 90 days. Multiple imputation was used for missing data. Backward elimination was performed with a P-value <0.10. Discrimination (c-statistic with 95% confidence intervals [CI] and prediction intervals [PI]) and calibration (outcome:expected [O:E] ratio and calibration plot) were evaluated based on internal-external cross-validation. The accuracy of the model was subsequently compared with algorithms based on the Wells score and D-dimer testing. The final model included age (in years), sex, previous VTE, recent surgery or immobilization, haemoptysis, cancer, clinical signs of deep vein thrombosis, inpatient status, D-dimer (in µg/L), and an interaction term between age and D-dimer. The pooled c-statistic was 0.87 (95% CI, 0.85-0.89; 95% PI, 0.77-0.93) and overall calibration was very good (pooled O:E ratio, 0.99; 95% CI, 0.87-1.14; 95% PI, 0.55-1.79). The model slightly overestimated VTE probability in the lower range of estimated probabilities. Discrimination of the current model in the validation data sets was better than that of the Wells score combined with a D-dimer threshold based on age (c-statistic 0.73; 95% CI, 0.70-0.75) or structured clinical pretest probability (c-statistic 0.79; 95% CI, 0.76-0.81). CONCLUSION: The present model provides an absolute, individualized probability of PE presence in a broad population of patients with suspected PE, with very good discrimination and calibration. Its clinical utility needs to be evaluated in a prospective management or impact study. REGISTRATION: PROSPERO ID 89366.

Diagnostic Performance of Physician Gestalt for Bacteremia in Patients in the Process of Being Admitted With Suspected Infection.

BACKGROUND: Due to potentially fatal consequences of missed bacteremia, blood cultures are often overused. While there are several prediction models that can be used to identify patients who truly need blood cultures, physicians often rely on their gestalt. We evaluated the diagnostic performance of physician gestalt for bacteremia in comparison with 2 existing prediction models: Takeshima and Shapiro. METHODS: The study enrolled consecutive adult patients with suspected infection who were in the process of being admitted to the general medicine department at 2 hospitals between April 2017 and January 2019. Attending physicians provided gestalt regarding risk of bacteremia (0%-100%). Patients with a <10% risk estimated via each strategy (ie, physician gestalt or 2 existing models) were categorized as bacteremia excluded (ie, blood cultures were considered unnecessary). Strategies were compared in terms of safety (proportion of patients with bacteremia among those classified as bacteremia excluded) and efficiency (proportion of patients classified as bacteremia excluded among the total cohort). RESULTS: Among 2014 patients, 292 (14.5%) were diagnosed with bacteremia. The safety of physician gestalt and the Takeshima and Shapiro models was 3.7% (95% confidence interval [CI], 2.2% to 5.7%), 6.5% (95% CI, 5.0% to 7.9%), and 10.8% (95% CI, 9.4% to 12.3%), whereas the efficiency of each strategy was 22.4% (95% CI, 22.5% to 26.3%), 52.7% (95% CI, 50.5% to 54.9%), and 87.8% (95% CI, 86.3% to 89.2%), respectively. CONCLUSIONS: Physician gestalt was safer but less efficient than existing models. Clinical prediction models could help reduce the overuse of blood cultures.

Manipulating the growth environment through co-culture to enhance stress tolerance and viability of probiotic strains in the gastrointestinal tract.

IMPORTANCE: The viability of probiotics in the human gastrointestinal tract is important, as some reports indicate that the health benefits of live bacteria are greater than those of dead ones. Therefore, the higher the viability of the probiotic strain, the better it may be. However, probiotic strains lose their viability due to gastrointestinal stress such as gastric acid and bile. This study provides an example of the use of co-culture or pH-controlled monoculture, which uses more stringent conditions (lower pH) than normal monoculture to produce probiotic strains that are more resistant to gastrointestinal stress. In addition, co-cultured beverages showed higher viability of the probiotic strain in the human gastrointestinal tract than monocultured beverages in our human study.

Identification of genes essential for bile acid resistance in the probiotic Lacticaseibacillus paracasei strain Shirota.

Bile acid resistance is crucial to allow probiotic strains to survive in the gastrointestinal tract and exert health-promoting effects on their hosts. Our aim here was to determine the mechanism of this resistance via a genetic approach by identifying the genes essential for bile acid resistance in Lacticaseibacillus paracasei strain Shirota (LcS). We generated 4649 transposon-inserted lines of L. paracasei YIT 0291, which has the same genome sequence as LcS but lacks the pLY101 plasmid, and we screened them for bile-acid-sensitive mutants. The growth of 14 mutated strains was strongly inhibited by bile acid, and we identified 10 genes that could be involved in bile acid resistance. Expression of these genes was not markedly induced by bile acid, suggesting that their homeostatic expression is important for exerting bile acid resistance. Two mutants in which the transposon was independently inserted into cardiolipin synthase (cls) genes, showed strong growth inhibition. Disruption of the cls genes in LcS caused decreased cardiolipin (CL) production and the accumulation of the precursor phosphatidylglycerol in bacterial cells. These data suggest that LcS possesses several mechanisms for exerting bile acid resistance, and that homeostatic CL production is among the factors most essential for this resistance.

Safety and Efficiency of Diagnostic Strategies for Ruling Out Pulmonary Embolism in Clinically Relevant Patient Subgroups : A Systematic Review and Individual-Patient Data Meta-analysis.

BACKGROUND: How diagnostic strategies for suspected pulmonary embolism (PE) perform in relevant patient subgroups defined by sex, age, cancer, and previous venous thromboembolism (VTE) is unknown. PURPOSE: To evaluate the safety and efficiency of the Wells and revised Geneva scores combined with fixed and adapted D-dimer thresholds, as well as the YEARS algorithm, for ruling out acute PE in these subgroups. DATA SOURCES: MEDLINE from 1 January 1995 until 1 January 2021. STUDY SELECTION: 16 studies assessing at least 1 diagnostic strategy. DATA EXTRACTION: Individual-patient data from 20 553 patients. DATA SYNTHESIS: Safety was defined as the diagnostic failure rate (the predicted 3-month VTE incidence after exclusion of PE without imaging at baseline). Efficiency was defined as the proportion of individuals classified by the strategy as "PE considered excluded" without imaging tests. Across all strategies, efficiency was highest in patients younger than 40 years (47% to 68%) and lowest in patients aged 80 years or older (6.0% to 23%) or patients with cancer (9.6% to 26%). However, efficiency improved considerably in these subgroups when pretest probability-dependent D-dimer thresholds were applied. Predicted failure rates were highest for strategies with adapted D-dimer thresholds, with failure rates varying between 2% and 4% in the predefined patient subgroups. LIMITATIONS: Between-study differences in scoring predictor items and D-dimer assays, as well as the presence of differential verification bias, in particular for classifying fatal events and subsegmental PE cases, all of which may have led to an overestimation of the predicted failure rates of adapted D-dimer thresholds. CONCLUSION: Overall, all strategies showed acceptable safety, with pretest probability-dependent D-dimer thresholds having not only the highest efficiency but also the highest predicted failure rate. From an efficiency perspective, this individual-patient data meta-analysis supports application of adapted D-dimer thresholds. PRIMARY FUNDING SOURCE: Dutch Research Council. (PROSPERO: CRD42018089366).

Ruling out pulmonary embolism across different healthcare settings: A systematic review and individual patient data meta-analysis.

BACKGROUND: The challenging clinical dilemma of detecting pulmonary embolism (PE) in suspected patients is encountered in a variety of healthcare settings. We hypothesized that the optimal diagnostic approach to detect these patients in terms of safety and efficiency depends on underlying PE prevalence, case mix, and physician experience, overall reflected by the type of setting where patients are initially assessed. The objective of this study was to assess the capability of ruling out PE by available diagnostic strategies across all possible settings. METHODS AND FINDINGS: We performed a literature search (MEDLINE) followed by an individual patient data (IPD) meta-analysis (MA; 23 studies), including patients from self-referral emergency care (n = 12,612), primary healthcare clinics (n = 3,174), referred secondary care (n = 17,052), and hospitalized or nursing home patients (n = 2,410). Multilevel logistic regression was performed to evaluate diagnostic performance of the Wells and revised Geneva rules, both using fixed and adapted D-dimer thresholds to age or pretest probability (PTP), for the YEARS algorithm and for the Pulmonary Embolism Rule-out Criteria (PERC). All strategies were tested separately in each healthcare setting. Following studies done in this field, the primary diagnostic metrices estimated from the models were the "failure rate" of each strategy-i.e., the proportion of missed PE among patients categorized as "PE excluded" and "efficiency"-defined as the proportion of patients categorized as "PE excluded" among all patients. In self-referral emergency care, the PERC algorithm excludes PE in 21% of suspected patients at a failure rate of 1.12% (95% confidence interval [CI] 0.74 to 1.70), whereas this increases to 6.01% (4.09 to 8.75) in referred patients to secondary care at an efficiency of 10%. In patients from primary healthcare and those referred to secondary care, strategies adjusting D-dimer to PTP are the most efficient (range: 43% to 62%) at a failure rate ranging between 0.25% and 3.06%, with higher failure rates observed in patients referred to secondary care. For this latter setting, strategies adjusting D-dimer to age are associated with a lower failure rate ranging between 0.65% and 0.81%, yet are also less efficient (range: 33% and 35%). For all strategies, failure rates are highest in hospitalized or nursing home patients, ranging between 1.68% and 5.13%, at an efficiency ranging between 15% and 30%. The main limitation of the primary analyses was that the diagnostic performance of each strategy was compared in different sets of studies since the availability of items used in each diagnostic strategy differed across included studies; however, sensitivity analyses suggested that the findings were robust. CONCLUSIONS: The capability of safely and efficiently ruling out PE of available diagnostic strategies differs for different healthcare settings. The findings of this IPD MA help in determining the optimum diagnostic strategies for ruling out PE per healthcare setting, balancing the trade-off between failure rate and efficiency of each strategy.

Completeness of reporting of clinical prediction models developed using supervised machine learning: a systematic review.

BACKGROUND: While many studies have consistently found incomplete reporting of regression-based prediction model studies, evidence is lacking for machine learning-based prediction model studies. We aim to systematically review the adherence of Machine Learning (ML)-based prediction model studies to the Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) Statement. METHODS: We included articles reporting on development or external validation of a multivariable prediction model (either diagnostic or prognostic) developed using supervised ML for individualized predictions across all medical fields. We searched PubMed from 1 January 2018 to 31 December 2019. Data extraction was performed using the 22-item checklist for reporting of prediction model studies ( www.TRIPOD-statement.org ). We measured the overall adherence per article and per TRIPOD item. RESULTS: Our search identified 24,814 articles, of which 152 articles were included: 94 (61.8%) prognostic and 58 (38.2%) diagnostic prediction model studies. Overall, articles adhered to a median of 38.7% (IQR 31.0-46.4%) of TRIPOD items. No article fully adhered to complete reporting of the abstract and very few reported the flow of participants (3.9%, 95% CI 1.8 to 8.3), appropriate title (4.6%, 95% CI 2.2 to 9.2), blinding of predictors (4.6%, 95% CI 2.2 to 9.2), model specification (5.2%, 95% CI 2.4 to 10.8), and model's predictive performance (5.9%, 95% CI 3.1 to 10.9). There was often complete reporting of source of data (98.0%, 95% CI 94.4 to 99.3) and interpretation of the results (94.7%, 95% CI 90.0 to 97.3). CONCLUSION: Similar to prediction model studies developed using conventional regression-based techniques, the completeness of reporting is poor. Essential information to decide to use the model (i.e. model specification and its performance) is rarely reported. However, some items and sub-items of TRIPOD might be less suitable for ML-based prediction model studies and thus, TRIPOD requires extensions. Overall, there is an urgent need to improve the reporting quality and usability of research to avoid research waste. SYSTEMATIC REVIEW REGISTRATION: PROSPERO, CRD42019161764.

Usefulness of computed tomography in the diagnosis of acute pyelonephritis in older patients suspected of infection with unknown focus.

BACKGROUND: In older adults, the diagnosis of acute pyelonephritis is challenging because of non-specific symptoms and false-positive urine test results. Few studies have investigated the diagnostic performance of computed tomography (CT) signs. PURPOSE: To evaluate the diagnostic performance of CT signs for acute pyelonephritis in older patients suspected of infection with unknown focus. MATERIAL AND METHODS: This cross-sectional study was conducted between 2015 and 2018. Patients aged ≥65 years who underwent blood cultures, urine culture, and non-contrast or contrast-enhanced CT on admission were included. Cases with clinically presumable infection focus before CT were excluded. Two radiologists blinded to clinical information independently reviewed five CT signs: perirenal fat stranding; pelvicalyceal wall thickening and enhancement; renal enlargement; thickening of Gerota's fascia; and area(s) of decreased attenuation. The final diagnoses were made by a clinical expert panel. RESULTS: Among 473 eligible patients, 61 were diagnosed with acute pyelonephritis. When the laterality of findings between the left and right kidneys were considered, the positive and negative likelihood ratios of perirenal fat stranding were 4.0 (95% confidence interval [CI] = 2.3-7.0) and 0.8 (95% CI = 0.7-0.9) in non-contrast CT, respectively. The other signs in non-contrast CT showed similar diagnostic performance with positive and negative likelihood ratios of 3.5-11.3 and 0.8-0.9, respectively. CONCLUSION: CT signs can help physicians diagnose acute pyelonephritis in older patients suspected of infection with unknown focus.

Long-Term Risk for Major Bleeding During Extended Oral Anticoagulant Therapy for First Unprovoked Venous Thromboembolism : A Systematic Review and Meta-analysis.

BACKGROUND: The long-term risk for major bleeding in patients receiving extended (beyond the initial 3 to 6 months) anticoagulant therapy for a first unprovoked venous thromboembolism (VTE) is uncertain. PURPOSE: To determine the incidence of major bleeding during extended anticoagulation of up to 5 years among patients with a first unprovoked VTE, overall, and in clinically important subgroups. DATA SOURCES: MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials from inception to 23 July 2021. STUDY SELECTION: Randomized controlled trials (RCTs) and prospective cohort studies reporting major bleeding among patients with a first unprovoked VTE who were to receive oral anticoagulation for a minimum of 6 additional months after completing at least 3 months of initial anticoagulant treatment. DATA EXTRACTION: Two reviewers independently abstracted data and assessed study quality. Unpublished data required for analyses were obtained from authors of included studies. DATA SYNTHESIS: Among the 14 RCTs and 13 cohort studies included in the analysis, 9982 patients received a vitamin K antagonist (VKA) and 7220 received a direct oral anticoagulant (DOAC). The incidence of major bleeding per 100 person-years was 1.74 events (95% CI, 1.34 to 2.20 events) with VKAs and 1.12 events (CI, 0.72 to 1.62 events) with DOACs. The 5-year cumulative incidence of major bleeding with VKAs was 6.3% (CI, 3.6% to 10.0%). Among patients receiving either a VKA or a DOAC, the incidence of major bleeding was statistically significantly higher among those who were older than 65 years or had creatinine clearance less than 50 mL/min, a history of bleeding, concomitant use of antiplatelet therapy, or a hemoglobin level less than 100 g/L. The case-fatality rate of major bleeding was 8.3% (CI, 5.1% to 12.2%) with VKAs and 9.7% (CI, 3.2% to 19.2%) with DOACs. LIMITATION: Data were insufficient to estimate incidence of major bleeding beyond 1 year of extended anticoagulation with DOACs. CONCLUSION: In patients with a first unprovoked VTE, the long-term risks and consequences of anticoagulant-related major bleeding are considerable. This information will help inform patient prognosis and guide decision making about treatment duration for unprovoked VTE. PRIMARY FUNDING SOURCE: Canadian Institutes of Health Research. (PROSPERO: CRD42019128597).

Accuracy of Ultrasound for Evaluation of Colorectal Segments in Patients With Inflammatory Bowel Diseases: A Systematic Review and Meta-analysis.

BACKGROUND & AIMS: The accuracy of ultrasound for evaluation of individual colorectal segments in patients with inflammatory bowel diseases (IBD) has not been evaluated in a systematic review. We evaluated the diagnostic accuracy of ultrasound in different colorectal segments of patients with IBD. METHODS: We searched publication databases from inception through March 2019 for studies that assessed the accuracy of ultrasound in detection of inflammation in right, transverse, and left colon and in rectum in patients with IBD, using findings from colonoscopy as the reference standard. Subgroup analyses were performed including IBD type, patient age, body mass index, and study design. The risk of bias was assessed with the Quality Assessment of Diagnostic Accuracy Studies-2 tool. RESULTS: Nineteen studies (1101 patients) were included in the qualitative synthesis. After we assessed the risk of bias, 7 studies (comprising 84 patients with Crohn's disease and 420 patients with ulcerative colitis) were included in the meta-analysis. Bowel wall thickness ≥ 3 mm identified colorectal segments with inflammation with 86.4% pooled sensitivity (95% CI, 76.1%-92.7%) and 88.3% pooled specificity (95% CI, 58.1%-97.6%). In rectum only, bowel wall thickness ≥ 3 mm identified inflammation with 74.5% sensitivity (95% CI, 53.0%-88.3%) and 69.5% specificity (95% CI, 33.6%-91.1%). Diagnostic accuracy was comparable among subgroups. Increased bowel wall flow and loss of stratification had higher true-positive odds ratios. CONCLUSIONS: Based on meta-analysis of patient-level data, ultrasound has higher diagnostic accuracy for detecting inflammation in colon than rectum in patients with IBD. Studies are needed to increase the accuracy of ultrasound detection of inflammation in rectum.

Impact of clinical information on CT diagnosis by radiologist and subsequent clinical management by physician in acute abdominal pain.

OBJECTIVE: The impact of clinical information on radiological diagnoses and subsequent clinical management has not been sufficiently investigated. This study aimed to compare diagnostic performance between radiological reports made with and without clinical information and to evaluate differences in the clinical management decisions based on each of these reports. METHODS: We retrospectively reviewed 410 patients who presented with acute abdominal pain and underwent unenhanced (n = 248) or enhanced CT (n = 162). Clinical information including age, sex, current and past history, physical findings, and laboratory tests were collected. Six radiologists independently interpreted CTs that were randomly assigned with or without clinical information, made radiological diagnoses, and scored the diagnostic confidence level. Four general and emergency physicians simulated clinical management (i.e., followed up in the outpatient clinic, hospitalized for conservative therapy, or referred to other departments for invasive therapy) based on reports made with or without the clinical information. Reference standards for the radiological diagnoses and clinical management were defined by an independent expert panel. RESULTS: The radiological diagnoses made with clinical information were more accurate than those made without clinical information (93.7% vs. 87.8%, p = 0.008). Median interpretation time for radiological reporting with clinical information was significantly shorter than that without clinical information (median 122.0 vs. 139.0 s, p < 0.001). Clinical simulation better matched the reference standard for clinical management when radiological diagnoses were made with reference to clinical information (97.3% vs. 87.8%, p < 0.001). CONCLUSION: Access to adequate clinical information enables accurate radiological diagnoses and appropriate subsequent clinical management of patients with acute abdominal pain. KEY POINTS: • Radiological interpretation improved diagnostic accuracy and confidence level when clinical information was provided. • Providing clinical information did not extend the interpretation time required by radiologists. • Radiological interpretation with clinical information led to correct clinical management by physicians.

The additional diagnostic impact of positron emission tomography-computed tomography for lymph node metastasis from colorectal cancer: A prospective lymph node level analysis.

BACKGROUND: We conducted a prospective study to determine the diagnostic performance of positron emission tomography-computed tomography (PET-CT) for lymph node metastasis in colorectal cancer patients. METHODS: We enrolled patients scheduled to receive curative surgery with lymph node dissection for colorectal adenocarcinoma who underwent contrast-enhanced abdominopelvic CT and PET-CT before surgery and who had primary lesions of cT2 or deeper. A radiologist determined the fluorodeoxyglucose uptake and the standardized uptake value (SUV) and metabolic volume (MV) to diagnose metastasis in cases with enlarged lymph nodes (≥7 mm long in minor diameter) on contrast-enhanced CT. Two gastrointestinal surgeons intraoperatively identified target lymph nodes to assess the association between images and pathological findings. The diagnostic performance (i.e., sensitivity, specificity, and positive and negative predictive values) for lymph node metastasis was determined using multilevel logistic modeling. RESULTS: A total of 205 colorectal cancer patients were enrolled from February 2018 to April 2020 and 194 patients were analyzed in this study. The sensitivity, specificity, and positive and negative predictive values of PET-CT were 15.3% (13.4%-17.5%), 100.0% (99.0%-100.0%), 100.0% (51.2%-100.0%), and 98.7% (98.5%-99.0%), respectively. CONCLUSION: PET-CT is a useful modality for determining the presence of metastasis in swollen lymph nodes on contrast-enhanced CT in colorectal cancer patients.

The comparative and added prognostic value of biomarkers to the Revised Cardiac Risk Index for preoperative prediction of major adverse cardiac events and all-cause mortality in patients who undergo noncardiac surgery.

BACKGROUND: The Revised Cardiac Risk Index (RCRI) is a widely acknowledged prognostic model to estimate preoperatively the probability of developing in-hospital major adverse cardiac events (MACE) in patients undergoing noncardiac surgery. However, the RCRI does not always make accurate predictions, so various studies have investigated whether biomarkers added to or compared with the RCRI could improve this. OBJECTIVES: Primary: To investigate the added predictive value of biomarkers to the RCRI to preoperatively predict in-hospital MACE and other adverse outcomes in patients undergoing noncardiac surgery. Secondary: To investigate the prognostic value of biomarkers compared to the RCRI to preoperatively predict in-hospital MACE and other adverse outcomes in patients undergoing noncardiac surgery. Tertiary: To investigate the prognostic value of other prediction models compared to the RCRI to preoperatively predict in-hospital MACE and other adverse outcomes in patients undergoing noncardiac surgery. SEARCH METHODS: We searched MEDLINE and Embase from 1 January 1999 (the year that the RCRI was published) until 25 June 2020. We also searched ISI Web of Science and SCOPUS for articles referring to the original RCRI development study in that period. SELECTION CRITERIA: We included studies among adults who underwent noncardiac surgery, reporting on (external) validation of the RCRI and: - the addition of biomarker(s) to the RCRI; or - the comparison of the predictive accuracy of biomarker(s) to the RCRI; or - the comparison of the predictive accuracy of the RCRI to other models. Besides MACE, all other adverse outcomes were considered for inclusion. DATA COLLECTION AND ANALYSIS: We developed a data extraction form based on the CHARMS checklist. Independent pairs of authors screened references, extracted data and assessed risk of bias and concerns regarding applicability according to PROBAST. For biomarkers and prediction models that were added or compared to the RCRI in ≥ 3 different articles, we described study characteristics and findings in further detail. We did not apply GRADE as no guidance is available for prognostic model reviews. MAIN RESULTS: We screened 3960 records and included 107 articles.   Over all objectives we rated risk of bias as high in ≥ 1 domain in 90% of included studies, particularly in the analysis domain. Statistical pooling or meta-analysis of reported results was impossible due to heterogeneity in various aspects: outcomes used, scale by which the biomarker was added/compared to the RCRI, prediction horizons and studied populations.  Added predictive value of biomarkers to the RCRI Fifty-one studies reported on the added value of biomarkers to the RCRI. Sixty-nine different predictors were identified derived from blood (29%), imaging (33%) or other sources (38%). Addition of NT-proBNP, troponin or their combination improved the RCRI for predicting MACE (median delta c-statistics: 0.08, 0.14 and 0.12 for NT-proBNP, troponin and their combination, respectively). The median total net reclassification index (NRI) was 0.16 and 0.74 after addition of troponin and NT-proBNP to the RCRI, respectively. Calibration was not reported. To predict myocardial infarction, the median delta c-statistic when NT-proBNP was added to the RCRI was 0.09, and 0.06 for prediction of all-cause mortality and MACE combined. For BNP and copeptin, data were not sufficient to provide results on their added predictive performance, for any of the outcomes. Comparison of the predictive value of biomarkers to the RCRI  Fifty-one studies assessed the predictive performance of biomarkers alone compared to the RCRI. We identified 60 unique predictors derived from blood (38%), imaging (30%) or other sources, such as the American Society of Anesthesiologists (ASA) classification (32%). Predictions were similar between the ASA classification and the RCRI for all studied outcomes. In studies different from those identified in objective 1, the median delta c-statistic was 0.15 and 0.12 in favour of  BNP and NT-proBNP alone, respectively, when compared to the RCRI, for the prediction of MACE. For C-reactive protein, the predictive performance was similar to the RCRI. For other biomarkers and outcomes, data were insufficient to provide summary results. One study reported on calibration and none on reclassification. Comparison of the predictive value of other prognostic models to the RCRI   Fifty-two articles compared the predictive ability of the RCRI to other prognostic models. Of these, 42% developed a new prediction model, 22% updated the RCRI, or another prediction model, and 37% validated an existing prediction model. None of the other prediction models showed better performance in predicting MACE than the RCRI. To predict myocardial infarction and cardiac arrest, ACS-NSQIP-MICA had a higher median delta c-statistic of 0.11 compared to the RCRI. To predict all-cause mortality, the median delta c-statistic was 0.15 higher in favour of ACS-NSQIP-SRS compared to the RCRI. Predictive performance was not better for CHADS2, CHA2DS2-VASc, R2CHADS2, Goldman index, Detsky index or VSG-CRI compared to the RCRI for any of the outcomes. Calibration and reclassification were reported in only one and three studies, respectively. AUTHORS' CONCLUSIONS: Studies included in this review suggest that the predictive performance of the RCRI in predicting MACE is improved when NT-proBNP, troponin or their combination are added. Other studies indicate that BNP and NT-proBNP, when used in isolation, may even have a higher discriminative performance than the RCRI. There was insufficient evidence of a difference between the predictive accuracy of the RCRI and other prediction models in predicting MACE. However, ACS-NSQIP-MICA and ACS-NSQIP-SRS outperformed the RCRI in predicting myocardial infarction and cardiac arrest combined, and all-cause mortality, respectively. Nevertheless, the results cannot be interpreted as conclusive due to high risks of bias in a majority of papers, and pooling was impossible due to heterogeneity in outcomes, prediction horizons, biomarkers and studied populations. Future research on the added prognostic value of biomarkers to existing prediction models should focus on biomarkers with good predictive accuracy in other settings (e.g. diagnosis of myocardial infarction) and identification of biomarkers from omics data. They should be compared to novel biomarkers with so far insufficient evidence compared to established ones, including NT-proBNP or troponins. Adherence to recent guidance for prediction model studies (e.g. TRIPOD; PROBAST) and use of standardised outcome definitions in primary studies is highly recommended to facilitate systematic review and meta-analyses in the future.

Is "pain before vomiting" useful?: Diagnostic performance of the classic patient history item in acute appendicitis.

BACKGROUND: In most surgical textbooks, it has been stated that pain almost always precedes vomiting in patients with appendicitis. However, the usefulness of this classic history item, "pain before vomiting", has been investigated in only one study nearly 50 years ago, in which the cause of abdominal pain could not be identified in more than 40% of patients. Accordingly, our objective was to evaluate the performance of pain before vomiting for the diagnosis of acute appendicitis in patients who presented with both acute abdominal pain and vomiting. METHODS: A retrospective chart review of adult outpatients with abdominal pain and vomiting at three acute care hospitals was performed. The reference standard for appendicitis was a CT scan evaluated by two radiologists. Diagnostic performance of pain before vomiting and the value it added to the Alvarado score were evaluated. RESULTS: Among 310 patients, 24 patients were diagnosed with appendicitis. Diagnostic performance of pain before vomiting was a sensitivity of 95.8% (95% confidence interval [CI] 79.8-99.3) and a specificity of 16.6% (95% CI 12.6-21.4). When combined with the Alvarado score, it ruled out appendicitis in an additional 12% (increased from 32% to 44%) of patients without any false negatives. CONCLUSIONS: "Pain before vomiting" is useful for ruling out appendicitis in patients with abdominal pain and vomiting.

Effect of tailoring anticoagulant treatment duration by applying a recurrence risk prediction model in patients with venous thromboembolism compared to usual care: A randomized controlled trial.

BACKGROUND: Patients with unprovoked (i.e., without the presence of apparent transient risk factors such as recent surgery) venous thromboembolism (VTE) are at risk of recurrence if anticoagulants are stopped after 3-6 months, yet their risk remains heterogeneous. Thus, prolonging anticoagulant treatment should be considered in high-risk patients, whereas stopping is likely preferred in those with a low predicted risk. The Vienna Prediction Model (VPM) could aid clinicians in estimating this risk, yet its clinical effects and external validity are currently unknown. The aim of this study was to investigate the clinical impact of this model on reducing recurrence risk in patients with unprovoked VTE, compared to usual care. METHODS AND FINDINGS: In a randomized controlled trial, the decision to prolong or stop anticoagulant treatment was guided by predicted recurrence risk using the VPM (n = 441), which was compared with usual care (n = 442). Patients with unprovoked VTE were recruited from local thrombosis services in the Netherlands (in Utrecht, Harderwijk, Ede, Amersfoort, Zwolle, Hilversum, Rotterdam, Deventer, and Enschede) between 22 July 2011 and 30 November 2015, with 24-month follow-up complete for all patients by early 2018. The primary outcome was recurrent VTE during 24 months of follow-up. Secondary outcomes included major bleeding and clinically relevant non-major (CRNM) bleeding. In the total study population of 883 patients, mean age was 55 years, and 507 (57.4%) were men. A total of 96 recurrent VTE events (10.9%) were observed, 46 in the intervention arm and 50 in the control arm (risk ratio 0.92, 95% CI 0.63-1.35, p = 0.67). Major bleeding occurred in 4 patients, 2 in each treatment arm, whereas CRNM bleeding occurred in 20 patients (12 in intervention arm versus 8 in control arm). The VPM showed good discriminative power (c-statistic 0.76, 95% CI 0.69-0.83) and moderate to good calibration, notably at the lower spectrum of predicted risk. For instance, in 284 patients with a predicted risk of >2% to 4%, the observed rate of recurrence was 2.5% (95% CI 0.7% to 4.3%). The main limitation of this study is that it did not enroll the preplanned number of 750 patients in each study arm due to declining recruitment rate. CONCLUSIONS: Our results show that application of the VPM in all patients with unprovoked VTE is unlikely to reduce overall recurrence risk. Yet, in those with a low predicted risk of recurrence, the observed rate was also low, suggesting that it might be safe to stop anticoagulant treatment in these patients. TRIAL REGISTRATION: Netherlands Trial Register NTR2680.

Daikenchuto for reducing postoperative ileus in patients undergoing elective abdominal surgery.

Reason for withdrawal: Serious breach of Cochrane's conflict of interest policy. A ruling by Cochrane's Funding Arbiters that a Cochrane Review has seriously breached Cochrane's conflict of interest policy.

Added value of inflammatory markers to vital signs to predict mortality in patients suspected of severe infection.

OBJECTIVE: To evaluate the added value of inflammatory markers to vital signs to predict mortality in patients suspected of severe infection. METHODS: This study was conducted at an acute care hospital (471-bed capacity). Consecutive adult patients suspected of severe infection who presented to either ambulatory care or the emergency department from April 2015 to March 2017 were retrospectively evaluated. A prognostic model for predicting 30-day in-hospital mortality based on previously established vital signs (systolic blood pressure, respiratory rate, and mental status) was compared with an extended model that also included four inflammatory markers (C-reactive protein, neutrophil-lymphocyte ratio, mean platelet volume, and red cell distribution width). Measures of interest were model fit, discrimination, and the net percentage of correctly reclassified individuals at the pre-specified threshold of 10% risk. RESULTS: Of the 1015 patients included, 66 (6.5%) died. The extended model including inflammatory markers performed significantly better than the vital sign model (likelihood ratio test: p < 0.001), and the c-index increased from 0.69 (range 0.67-0.70) to 0.76 (range 0.75-0.77) (p = 0.01). All included markers except C-reactive protein showed significant contribution to the model improvement. Among those who died, 9.1% (95% CI -2.8-21.8) were correctly reclassified by the extended model at the 10% threshold. CONCLUSIONS: The inflammatory markers except C-reactive protein showed added predictive value to vital signs. Future studies should focus on developing and validating prediction models for use in individualized predictions including both vital signs and the significant markers.

Determinants of incentive preferences for health behavior change in Japan.

Interest in the use of incentives to promote health behavior change has been growing worldwide. However, to develop an effective incentive program, accurate information regarding individual preferences is essential. Therefore, the aim of this study was to clarify determinants of incentive preferences for health behavior change. A self-completed questionnaire survey regarding incentives for health behavior change was conducted in a Japanese village in 2015. The outcome measures were individual preferences for features of incentives, including item, frequency, type and value. The types of incentives were defined as follows: assured-type (given for participation); effort-type (given if participants make some kind of effort); and outcome-type (given if participants make achievements decided a priori). The associations with respondents' sex, age, presence of lifestyle-related disease and stage in the transtheoretical model of health behavior change were investigated using multivariate analysis. A total of 1469 residents responded to the survey. Significant associations with preference for different incentive features were found as follows: for monetary items, female and elderly; for high frequency, female and maintenance stage; for effort-type, male, action stage and contemplation stage; and for outcome-type, maintenance stage and action stage. Our results appeared to identify determinants of incentive preferences for health behavior change. These findings are expected to promote the development of an incentive program more in tune with individual preferences.

Daikenchuto for reducing postoperative ileus in patients undergoing elective abdominal surgery.

BACKGROUND: Postoperative ileus is a major complication for persons undergoing abdominal surgery. Daikenchuto, a Japanese traditional medicine (Kampo), is a drug that may reduce postoperative ileus. OBJECTIVES: To assess the efficacy and safety of Daikenchuto for reducing prolonged postoperative ileus in persons undergoing elective abdominal surgery. SEARCH METHODS: We searched the following databases on 3 July 2017: CENTRAL, MEDLINE, Embase, ICHUSHI, WHO (World Health Organization) International Clinical Trials Registry Platform (ICTRP), EU Crinical Trials registry (EU-CTR), UMIN Clinical Trials Registry (UMIN-CTR), ClinicalTrials.gov, The Japan Society for Oriental Medicine (JSOM), American Society of Clinical Oncology (ASCO), Society of American Gastrointestinal and Endscopic Surgeons (SAGES). We set no limitations on language or date of publication. SELECTION CRITERIA: We included randomised controlled trials (RCTs) comparing Daikenchuto with any control condition in adults, 18 years of age or older, undergoing elective abdominal surgery. DATA COLLECTION AND ANALYSIS: We applied standard methodological procedures expected by Cochrane. Two review authors independently reviewed the articles identified by literature searches, extracted data, and assessed risk of bias of the included studies using the Cochrane software Review Manager 5. MAIN RESULTS: We included seven RCTs with a total of 1202 participants. Overall, we judged the risk of bias as low in four studies and high in three studies. We are uncertain whether Daikenchuto reduced time to first flatus (mean difference (MD) -11.32 hours, 95% confidence interval (CI) -17.45 to -5.19; two RCTs, 83 participants; very low-quality evidence), or time to first bowel movement (MD -9.44 hours, 95% CI -22.22 to 3.35; four RCTs, 500 participants; very low-quality evidence) following surgery. There was little or no difference in time to resumption of regular solid food following surgery (MD 3.64 hours, 95% CI -24.45 to 31.74; two RCTs, 258 participants; low-quality evidence). There were no adverse events in either arm of the five RCTs that reported on drug-related adverse events (risk difference (RD) 0.00, 95% CI -0.02 to 0.02, 568 participants, low-quality evidence). We are uncertain of the effect of Daikenchuto on patient satisfaction (MD 0.09, 95% CI -0.19 to 0.37; one RCT, 81 participants; very low-quality of evidence). There was little or no difference in the incidence of any re-interventions for postoperative ileus before leaving hospital (risk ratio (RR) 0.99, 95% CI 0.06 to 15.62; one RCT, 207 participants; moderate-quality evidence), or length of hospital stay (MD -0.49 days, 95% CI -1.21 to 0.22; three RCTs, 292 participants; low-quality evidence). AUTHORS' CONCLUSIONS: Evidence from current literature was unclear whether Daikenchuto reduced postoperative ileus in patients undergoing elective abdominal surgery, due to the small number of participants in the meta-analyses. Very low-quality evidence means we are uncertain whether Daikenchuto improved postoperative flatus or bowel movement. Further well-designed and adequately powered studies are needed to assess the efficacy of Daikenchuto.