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排序方式: 共有3023条查询结果,搜索用时 15 毫秒
41.
Desiree M.J. Dorleijn Pim A.J. Luijsterburg Sita M.A. Bierma-Zeinstra Pieter K. Bos 《The Journal of arthroplasty》2014
To assess the diagnostic value of intra-articular anesthetic hip injection in patients with hip pain atypical for osteoarthritis (OA), literature was searched. Included were studies assessing the diagnostic value of anesthetic hip injections in differentiating between pain caused by OA or another source. Pooled estimates of sensitivity and specificity with 95% confidence intervals (CI) were calculated. Of the 1387 potentially eligible articles, nine case series with high risk of bias could be included. The pooled sensitivity was 0.97 (95% CI 0.87, 0.99). Specificity was 0.91 (95% CI 0.83, 0.95). For clinical practice, no recommendation can be made regarding the use of hip injections for diagnosing hip OA. High quality, accurately reported studies are needed to provide better evidence on the diagnostic role of hip injection. 相似文献
42.
《Annals of epidemiology》2017,27(8):466-471.e2
PurposeDescribe the relative frequency and joint effect of missing and misreported fetal death certificate (FDC) data and identify variations by key characteristics.MethodsStillbirths were prospectively identified during 2006–2008 for a multisite population-based case-control study. For this study, eligible mothers of stillbirths were not incarcerated residents of DeKalb County, Georgia, or Salt Lake County, Utah, aged ≥13 years, with an identifiable FDC. We identified the frequency of missing and misreported (any departure from the study value) FDC data by county, race/ethnicity, gestational age, and whether the stillbirth was antepartum or intrapartum.ResultsData quality varied by item and was highest in Salt Lake County. Reporting was generally not associated with maternal or delivery characteristics. Reasons for poor data quality varied by item in DeKalb County: some items were frequently missing and misreported; however, others were of poor quality due to either missing or misreported data.ConclusionsFDC data suffer from missing and inaccurate data, with variations by item and county. Salt Lake County data illustrate that high quality reporting is attainable. The overall quality of reporting must be improved to support consequential epidemiologic analyses for stillbirth, and improvement efforts should be tailored to the needs of each jurisdiction. 相似文献
43.
A. Pfützner C. Hengesbach F. Demircik C. Schipper T. Forst P.B. Musholt 《Current medical research and opinion》2014,30(2):185-190
Since 2003, blood glucose meters for patient self testing are approved in Europe based on the accuracy performance criteria as defined by the ISO15197 guideline. A new draft ISO guideline is currently under regulatory review, which suggests more strict accuracy acceptance criteria, and which may not be entirely fulfilled by currently commercialized blood glucose meter systems. In order to investigate the compliance of BG*Star and iBG*Star and several other blood glucose meters with the new draft ISO guideline, we performed a post-hoc analysis of data obtained from a recently performed ISO-conforming clinical accuracy performance study. This study was performed with 106 patients, clinically presenting with blood glucose levels distributed over the entire measurement range and in line with the glucose distribution requirements as demanded by the guideline. The YSI 2300 STAT Plus analyzer (glucose oxidase) served as reference method.While all tested meters had been in a high degree of compliance with the current ISO criteria, performance was lower when analyzed in accordance with the new acceptance criteria (95% of readings have to be within ±15?mg/dL for values <100?mg/dL, and within ±15% for values ≥100?mg/dL). The following meters met the new criteria: Accu-Chek Aviva (95.5%/98.6%), BG*Star (98.5%/97.3%), iBG*Star (98.5%/97.3%), FreeStyle Freedom Lite (95.5%/96.6%), and OneTouch Ultra2 (95.5%/96.5%). One meter failed with low blood glucose values (Contour: 90.9%/95.9%).In conclusion, BG*Star and iBG*Star and several other branded meters met the new draft ISO15197 acceptance criteria, when tested in accordance with the instructions for use and with the ISO accuracy testing protocol in a clinical setting. 相似文献
44.
45.
《Injury》2018,49(3):457-466
ObjectiveTo assess the accuracy of the chest ultrasonography for the emergency diagnosis of traumatic pneumothorax and haemothorax in adults.Study designSystematic review and meta-analysis.MethodsPubMed, EMBASE, Scopus, Web of Science and LILACS (up to 2016) were systematically searched for prospective studies on the diagnostic accuracy of ultrasonography for pneumothorax and haemothorax in adult trauma patients. The references of other systematic reviews and the included studies were checked for further articles. The characteristics and results of the studies were extracted using a standardised form, and their methodological quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2). Primary analysis was performed considering each hemithorax as an independent unit, while secondary analysis considered each patient. The global diagnostic accuracy of the chest ultrasonography was estimated using the Rutter–Gatsonis hierarchical summary ROC method. Moreover, Reitsma’s bivariate model was used to estimate the sensitivity, specificity, positive likelihood ratio (LR + ) and negative likelihood ratio (LR–) of each sonographic sign. This review was previously registered (PROSPERO CRD42016048085).ResultsNineteen studies were included in the review, 17 assessing pneumothorax and 5 assessing haemothorax. The reference standard was always chest tomography, alone or in parallel with chest radiography and observation of the chest tube. The overall methodological quality of the studies was low. The diagnostic accuracy of chest ultrasonography had an area under the curve (AUC) of 0.979 for pneumothorax (Fig). The absence of lung sliding and comet-tail artefacts was the most reported sonographic sign of pneumothorax, with a sensitivity of 0.81 (95% confidence interval [95%CI], 0.71–0.88), specificity of 0.98 (95%CI, 0.97–0.99), LR+ of 67.9 (95%CI, 26.3–148) and LR– of 0.18 (95%CI, 0.11–0.29). An echo-poor or anechoic area in the pleural space was the only sonographic sign for haemothorax, with a sensitivity of 0.60 (95%CI, 0.31–0.86), specificity of 0.98 (95%CI, 0.94–0.99), LR+ of 37.5 (95%CI, 5.26–207.5), LR– of 0.40 (95%CI, 0.17–0.72) and AUC of 0.953.ConclusionNotwithstanding the limitations of the included studies, this systematic review and meta-analysis suggested that chest ultrasonography is an accurate tool for the diagnostic assessment of traumatic pneumothorax and haemothorax in adults. 相似文献
46.
47.
《Evidence-Based Communication Assessment and Intervention》2013,7(1):34-45
Clinicians have always been aware of the importance of using valid and reliable clinical tests and measures—and of avoiding those that are not. However, the choice of which tests and measures to use is often more a matter of personal preference, arising out of knowledge of a test's psychometric properties and one's experience with the test, rather than being based on a systematic, critical appraisal of assessment tools. This paper proposes a method of critically appraising clinical assessments in the speech and language sciences, for the purpose of deciding whether they are likely to be informative in diagnosing individuals with communication disorders. QUADAS (Quality Assessment of Diagnostic Accuracy Studies)—a 14-item, evidence-based critical appraisal tool (Whiting, Rutjes, Reitsma, Bossuyt,?&?Kleijnen, 2003) originally designed to assess the quality of diagnostic-accuracy studies used in systematic reviews in medicine—is presented, with an example of how it can be applied in the field of communication disorders. 相似文献
48.
Asymptotic Structure of Cosmological Burgers Flows in One and Two Space Dimensions: A Numerical Study 下载免费PDF全文
Yangyang Cao Mohammad A. Ghazizadeh & Philippe G. LeFloch 《Communications In Computational Physics》2021,29(2):472-509
We study the cosmological Burgers model, as we call it, which is a nonlinear
hyperbolic balance law (in one and two spatial variables) posed on an expanding or
contracting background. We design a finite volume scheme that is fourth-order in
time and second-order in space, and allows us to compute weak solutions containing
shock waves. Our main contribution is the study of the asymptotic structure of the
solutions as the time variable approaches infinity (in the expanding case) or zero (in
the contracting case). We discover that a saddle competition is taking place which
involves, on one hand, the geometrical effects of expanding or contracting nature and,
on the other hand, the nonlinear interactions between shock waves. 相似文献
49.
《Journal of neuroradiology. Journal de neuroradiologie》2020,47(6):433-440
Purpose and backgroundThis study retrospectively compares diagnostic performance of 1.5 T versus 3 T non-echo planar diffusion weighted imaging with or without additional T1 and T2 sequences in the detection of residual and/or recurrent cholesteatoma.MethodsPatients with clinically suspected recurrent cholesteatoma or postoperative routine survey MR who subsequently underwent surgical procedure were retrospectively included (135 patients, 164 operated ears) from a large database. Patients underwent 1.5 T (128 ears) or 3 T MRI (36 ears), with non-echo planar DWI, T1 and T2 acquisitions. Two radiologists independently reassessed the images. Definitive surgical diagnosis was used as gold standard. Sensitivity, specificity and diagnostic odds ratio were evaluated.ResultsAccording to surgical diagnosis a cholesteatoma was present in 124 of 164 ears, corresponding with a prevalence of 75%. Sensitivity and specificity were lower for 3 T compared to 1.5 T, irrespective of whether additional T1 and T2-weighted sequences were used or not. Diagnostic odds ratios were higher for 1.5 T (34 and 12 for reader 1 and 2, respectively) compared to 3 T (3 and 4 for reader 1 and 2, respectively). Adding T1 and T2 sequences lowers sensitivity but increases specificity.ConclusionNon-epi DWI for the detection of residual/recurrent cholesteatoma is preferably performed on 1.5 T scanners over 3 T. The use of additional sequences regarding detection of cholesteatoma is debatable as it lowers sensitivity but increases specificity. However, these sequences may also be of use in diagnosing complications and planning surgical procedures in some hospitals. 相似文献
50.
《Journal of Cardiovascular Computed Tomography》2022,16(5):397-403
BackgroundPretest probability (PTP) calculators utilize epidemiological-level findings to provide patient-level risk assessment of obstructive coronary artery disease (CAD). However, their limited accuracies question whether dissimilarities in risk factors necessarily result in differences in CAD. Using patient similarity network (PSN) analyses, we wished to assess the accuracy of risk factors and imaging markers to identify ≥50% luminal narrowing on coronary CT angiography (CCTA) in stable chest-pain patients.MethodsWe created four PSNs representing: patient characteristics, risk factors, non-coronary imaging markers and calcium score. We used spectral clustering to group individuals with similar risk profiles. We compared PSNs to a contemporary PTP score incorporating calcium score and risk factors to identify ≥50% luminal narrowing on CCTA in the CT-arm of the PROMISE trial. We also conducted subanalyses in different age and sex groups.ResultsIn 3556 individuals, the calcium score PSN significantly outperformed patient characteristic, risk factor, and non-coronary imaging marker PSNs (AUC: 0.81 vs. 0.57, 0.55, 0.54; respectively, p ?< ?0.001 for all). The calcium score PSN significantly outperformed the contemporary PTP score (AUC: 0.81 vs. 0.78, p ?< ?0.001), and using 0, 1–100 and ?> ?100 cut-offs provided comparable results (AUC: 0.81 vs. 0.81, p ?= ?0.06). Similar results were found in all subanalyses.ConclusionCalcium score on its own provides better individualized obstructive CAD prediction than contemporary PTP scores incorporating calcium score and risk factors. Risk factors may not be able to improve the diagnostic accuracy of calcium score to predict ≥50% luminal narrowing on CCTA. 相似文献