323 research outputs found
External Validation of Prediction Models for Pneumonia in Primary Care Patients with Lower Respiratory Tract Infection: An Individual Patient Data Meta-Analysis
BackgroundPneumonia remains difficult to diagnose in primary care. Prediction models based on signs and symptoms (S&S) serve to minimize the diagnostic uncertainty. External validation of these models is essential before implementation into routine practice. In this study all published S&S models for prediction of pneumonia in primary care were externally validated in the individual patient data (IPD) of previously performed diagnostic studies.Methods and findingsS&S models for diagnosing pneumonia in adults presenting to primary care with lower respiratory tract infection and IPD for validation were identified through a systematical search. Six prediction models and IPD of eight diagnostic studies (N total = 5308, prevalence pneumonia 12%) were included. Models were assessed on discrimination and calibration. Discrimination was measured using the pooled Area Under the Curve (AUC) and delta AUC, representing the performance of an individual model relative to the average dataset performance. Prediction models by van Vugt et al. and Heckerling et al. demonstrated the highest pooled AUC of 0.79 (95% CI 0.74-0.85) and 0.72 (0.68-0.76), respectively. Other models by Diehr et al., Singal et al., Melbye et al., and Hopstaken et al. demonstrated pooled AUCs of 0.65 (0.61-0.68), 0.64 (0.61-0.67), 0.56 (0.49-0.63) and 0.53 (0.5-0.56), respectively. A similar ranking was present based on the delta AUCs of the models. Calibration demonstrated close agreement of observed and predicted probabilities in the models by van Vugt et al. and Singal et al., other models lacked such correspondence. The absence of predictors in the IPD on dataset level hampered a systematical comparison of model performance and could be a limitation to the study.ConclusionsThe model by van Vugt et al. demonstrated the highest discriminative accuracy coupled with reasonable to good calibration across the IPD of different study populations. This model is therefore the main candidate for primary care use
Living-donor parathyroid allotransplantation for therapy-refractory postsurgical persistent hypoparathyroidism in a nontransplant recipient – three year results: a case report
Limitations of Tc99m-MIBI-SPECT Imaging Scans in Persistent Primary Hyperparathyroidism
In primary hyperparathyroidism (PHPT) the predictive value of technetium 99m sestamibi single emission computed tomography (Tc99m-MIBI-SPECT) for localizing pathological parathyroid glands before a first parathyroidectomy (PTx) is 83-100%. Data are scarce in patients undergoing reoperative parathyroidectomy for persistent hyperparathyroidism. The aim of the present study was to determine the value of Tc99m-MIBI-SPECT in localizing residual hyperactive parathyroid tissue in patients with persistent primary hyperparathyroidism (PHPT) after initial excision of one or more pathological glands. We retrospectively evaluated the localizing accuracy of Tc99m-MIBI-SPECT scans in 19 consecutive patients with persistent PHPT who had a scan before reoperative parathyroidectomy. We used as controls 23 patients with sporadic PHPT who had a scan before initial surgery. In patients with persistent PHPT, Tc99m-MIBI-SPECT accurately localized a pathological parathyroid gland in 33% of cases before reoperative parathyroidectomy, compared to 61% before first PTx for sporadic PHPT. The Tc99m-MIBI-SPECT scan accurately localized intra-thyroidal glands in 2 of 7 cases and a mediastinal gland in 1 of 3 cases either before initial or reoperative parathyroidectomy. Our data suggest that the accuracy of Tc99m-MIBI-SPECT in localizing residual hyperactive glands is significantly lower before reoperative parathyroidectomy for persistent PHPT than before initial surgery for sporadic PHPT. These findings should be taken in consideration in the preoperative workup of patients with persistent primary hyperparathyroidis
Physicians Report Barriers to Deliver Best Practice Care for Asplenic Patients: A Cross-Sectional Survey
Background: Current management of asplenic patients is not in compliance with best practice standards, such as defined by the British Committee for Standards in Haematology. To improve quality of care, factors inhibiting best practice care delivery need to be identified first. With this study, we aimed to identify and quantify physicians' barriers to adhere to best practice management of asplenic patients in the Netherlands. Methods and Principal Findings: A cross-sectional survey, preceded by multiple focus group discussions, was performed among Dutch physicians responsible for prevention of infections in asplenic patients, including specialists ( of Internal medicine and Surgery) and general practitioners (GPs). Forty seven GPs and seventy three hospital specialists returned the questionnaire, yielding response rates of 47% and 36,5% respectively. Physicians reported several barriers to deliver best practice. For both GPs and specialists, the most frequently listed barriers were: poor patient knowledge (> 80% of hospital specialists and GPs) and lack of clarity about which physician is responsible for the management of asplenic patients (50% of Internists, 46% of Surgeons, 55% of GPs). Both GPs and hospital specialists expressed to experience a lack of mutual trust: specialists were uncertain whether the GP would follow their advice given on patient discharge (33-59%), whereas half of GPs was not convinced that specialists' discharge letters contained the correct recommendations. Almost all physicians (> 90%) indicated that availability of a national guideline would improve adherence to best practice, especially if accessible online. Conclusion: This study showed that, in accordance with reports on international performance, care delivery for asplenic patients in the Netherlands is suboptimal. We identified and quantified perceived barriers by physicians that prevent adherence to post-splenectomy guidelines for the first time. Better transmural collaboration and better informed patients are likely to improve the quality of care of the asplenic patient population. A national, online-available guideline is urgently require
Low oxygen saturation and mortality in an adult cohort; the Tromsø Study
Published version, also available at http://dx.doi.org/10.1186/s12890-015-0003-5Background: Oxygen saturation has been shown in risk score models to predict mortality in emergency medicine.
The aim of this study was to determine whether low oxygen saturation measured by a single-point measurement
by pulse oximetry (SpO2) is associated with increased mortality in the general adult population.
Methods: Pulse oximetry was performed in 5,152 participants in a cross-sectional survey in Tromsø, Norway, in
2001–2002 (“Tromsø 5”). Ten-year follow-up data for all-cause mortality and cause of death were obtained from the
National Population and the Cause of Death Registries, respectively. Cause of death was grouped into four categories:
cardiovascular disease, cancer except lung cancer, pulmonary disease, and others. SpO2 categories were assessed as
predictors for all-cause mortality and death using Cox proportional-hazards regression models after correcting for age,
sex, smoking history, body mass index (BMI), C-reactive protein level, self-reported diseases, respiratory symptoms, and
spirometry results.
Results: The mean age was 65.8 years, and 56% were women. During the follow-up, 1,046 (20.3%) participants died.
The age- and sex-adjusted hazard ratios (HRs) (95% confidence intervals) for all-cause mortality were 1.99 (1.33–2.96)
for SpO2 ≤ 92% and 1.36 (1.15–1.60) for SpO2 93–95%, compared with SpO2 ≥ 96%. In the multivariable Cox
proportional-hazards regression models that included self-reported diseases, respiratory symptoms, smoking
history, BMI, and CRP levels as the explanatory variables, SpO2 remained a significant predictor of all-cause
mortality. However, after including forced expiratory volume in 1 s percent predicted (FEV1% predicted), this
association was no longer significant. Mortality caused by pulmonary diseases was significantly associated with
SpO2 even when FEV1% predicted was included in the model.
Conclusions: Low oxygen saturation was independently associated with increased all-cause mortality and
mortality caused by pulmonary diseases. When FEV1% predicted was included in the analysis, the strength of
the association weakened but was still statistically significant for mortality caused by pulmonary diseases
External validation of the PAGE-B score for HCC risk prediction in people living with HIV/HBV coinfection
Background & Aims: HBV coinfection is common among people living with HIV (PLWH) and is the most important cause of hepatocellular carcinoma (HCC). While risk prediction tools for HCC have been validated in patients with HBV monoinfection, they have not been evaluated in PLWH. Thus, we performed an external validation of PAGE-B in people with HIV/HBV coinfection. Methods: We included data on PLWH from four European cohorts who were positive for HBsAg and did not have HCC before starting tenofovir. We estimated the predictive performance of PAGE-B for HCC occurrence over 15 years in patients receiving tenofovir-containing antiretroviral therapy. Model discrimination was assessed after multiple imputation using Cox regression with the prognostic index as a covariate, and by calculating Harrell's c-index. Calibration was assessed by comparing our cumulative incidence with the PAGE-B derivation study using Kaplan-Meier curves. Results: In total, 2,963 individuals with HIV/HBV coinfection on tenofovir-containing antiretroviral therapy were included. PAGE-B was <10 in 26.5%, 10–17 in 57.7%, and ≥18 in 15.7% of patients. Within a median follow-up of 9.6 years, HCC occurred in 68 individuals (2.58/1,000 patient-years, 95% CI 2.03–3.27). The regression slope of the prognostic index for developing HCC within 15 years was 0.93 (95% CI 0.61–1.25), and the pooled c-index was 0.77 (range 0.73–0.80), both indicating good model discrimination. The cumulative incidence of HCC was lower in our study compared to the derivation study. A PAGE-B cut-off of <10 had a negative predictive value of 99.4% for the development of HCC within 5 years. Restricting efforts to individuals with a PAGE-B of ≥10 would spare unnecessary HCC screening in 27% of individuals. Conclusions: For individuals with HIV/HBV coinfection, PAGE-B is a valid tool to determine the need for HCC screening. Impact and implications: Chronic HBV infection is the most important cause of hepatocellular carcinoma (HCC) among people living with HIV. Valid risk prediction may enable better targeting of HCC screening efforts to high-risk individuals. We aimed to validate PAGE-B, a risk prediction tool that is based on age, sex, and platelets, in 2,963 individuals with HIV/HBV coinfection who received tenofovir-containing antiretroviral therapy. In the present study, PAGE-B showed good discrimination, adequate calibration, and a cut-off of <10 had a negative predictive value of 99.4% for the development of HCC within 5 years. These results indicate that PAGE-B is a simple and valid risk prediction tool to determine the need for HCC screening among people living with HIV and HBV
Advancing research and practice in HIV and rehabilitation: a framework of research priorities in HIV, disability and rehabilitation
Measurement of D s <sup>±</sup> production asymmetry in pp collisions at √s=7 and 8 TeV
The inclusive production asymmetry is measured in collisions
collected by the LHCb experiment at centre-of-mass energies of
and 8 TeV. Promptly produced mesons are used, which decay as
, with . The measurement is
performed in bins of transverse momentum, , and rapidity, ,
covering the range GeV and . No kinematic
dependence is observed. Evidence of nonzero production asymmetry is
found with a significance of 3.3 standard deviations.Comment: All figures and tables, along with any supplementary material and
additional information, are available at
https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2018-010.htm
Gender differences in the use of cardiovascular interventions in HIV-positive persons; the D:A:D Study
Peer reviewe
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