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991.
BackgroundAdvances in fetal echocardiography training among pediatric cardiologists have led to substantial improvements in prenatal detection of congenital heart diseases (CHDs). Nevertheless, diagnostic accuracy varies among centers. Moreover, this subspecialty continues to evolve in developing countries, with limited studies assessing fetal echocardiography sensitivity, specificity, and accuracy in developing countries such as Egypt.Subject and methodsHigh-risk pregnancies referred for fetal echocardiography from January 2011 to January 2019 were analyzed retrospectively. All of the cases included had one of the high-risk indications for fetal echocardiography. Maternal age and gestational age at the prenatal diagnosis were determined, and detailed fetal and neonatal echocardiograms were documented. The results of fetal and postnatal echocardiography were compared to assess the sensitivity, specificity, and accuracy of fetal echocardiography. A minor lesion was defined when no postnatal intervention was needed and a major anomaly when postnatal cardiac therapy, surgery, or intervention was required.ResultsOut of 615 pregnant patients referred, comparisons between fetal and neonatal echocardiography were possible in 458 fetuses, with 157 patients excluded from the study. The mean maternal age in the study was 26.97 ± 5.871 years and the mean gestational age at referral was 27.24 ± 5.407 weeks. The most common indication for prenatal echocardiography in this cohort was a family history of CHD (142; 31%) followed by nonimmune hydrops (97; 21.18%) and abnormal obstetrical ultrasound screening (64; 13.97%). We had three false-positive minor diagnoses and four false-negative cases with only one requiring intervention. Prenatal diagnosis in this study was accurate in 98.47% of cases. The sensitivity, specificity, and accuracy of fetal echocardiography in the current work were 97.03%, 99.07%, and 98.47, respectively.ConclusionFetal echocardiography is considered a highly sensitive specific tool for prenatal detection of congenital heart diseases in high-risk pregnancies even in developing countries. However, minor fetal cardiac disorders are challenging to diagnose and family counseling should emphasize the difficulty of excluding or confirming such lesions. 相似文献
992.
《Journal of anxiety disorders》2014,28(2):280-282
Although dental phobia is classified under the heading of blood–injury phobia, studies show differences between the two conditions in terms of frequency of fainting and gender distribution. Anxiety sensitivity (AS), which refers to discomfort and negative attributions to bodily anxiety sensations, was useful in differentiating panic anxiety from other phobic anxieties. No study has compared dental phobia with blood–injury phobia directly. We examined 61 subjects, working at a military aircraft factory, using measures on demographics, dental fears (MDAS – Modified Dental Anxiety Scale) and blood–injury fears (MBPI – Multidimensional Blood/Injury Phobia Inventory), in addition to Anxiety Sensitivity Index. Regression analyses revealed that dental phobia was predicted by ASI, whereas blood/injury phobia was not. Our results provide additional support for the proposed distinction between the two conditions. 相似文献
993.
BackgroundAs primary HPV screening programs are rolled out, methods are needed for routine quality assurance of HPV laboratory analyzes.ObjectiveTo explore the use of similar design for audit as currently used in cytology-based screening, to estimate the clinical sensitivity to identify women at risk for CIN 3 or worse (CIN3+).Study designPopulation-based cohort study conducted within the cervical screening program in Stockholm, Sweden, in 2011–2012. All women with histopathologically confirmed CIN3+ in the following two years were identified by registry analysis. Primary HPV and cytology screening results were collected. For women who had not been HPV tested, biobanked cytology samples were HPV-tested. If the original HPV result had been negative, the sample and subsequent biopsies were analyzed with broad HPV typing (general primer PCR and Luminex).Results154 women had a biobanked prediagnostic cytology sample taken up to 2 years before a histopathologically confirmed CIN3+. The high-risk HPV-positivity was 97% (148/154 women), whereas 143/154 (94%) women had had a cytological abnormality. Among the six HPV-negative samples, one sample was HPV 33 positive in repeat testing whereas the other five cases were HPV-negative also on repeat testing, but HPV-positive in the subsequent tumor tissue.ConclusionsA sensitivity of the HPV test that is higher than the sensitivity of cytology suggests adequate quality of the testing. Regular audits of clinical sensitivity, similar to those of cytology-based screening, should be used also in HPV-based screening programs, in order to continuously monitor the performance of the analyzes. 相似文献
994.
《Actas urologicas espa?olas》2014,38(9):566-570
BackgroundTo evaluate the diagnostic usefulness of the cytological study of the transport buffer in the diagnosis of prostate adenocarcinoma in transrectal core biopsies.MethodsA total of 256 consecutively biopsied patients have been included in the analysis, 100 of them diagnosed of prostate adenocarcinoma. The procedure included the cytological analysis of the transport buffer and conventional histology. Cytological evaluation was performed in a blind way by the same pathologist.ResultsOverall sensitivity, specificity, and positive and negative predictive values to detect malignancy in the cytological slides were 54%, 98%, 94% and 76%, respectively. When restricted the analysis to cases with Gleason score higher than 8, sensitivity and negative predictive value increased to 85% and 97%, respectively. Similarly, when the analysis focused exclusively to cases with more than 5 mm of cancer in the biopsy, sensitivity and positive predictive value increased to 66% and 96%, respectively.ConclusionsThis study shows that whilst specificity was maintained in 98%, sensitivity, and positive and negative predictive values significantly improved in high grade and high volume adenocarcinomas. Our findings confirm that the cytological study of the transport buffer may complement the histology in the diagnosis of prostate adenocarcinoma. 相似文献
995.
目的 探讨64层螺旋CT在早期诊断原发性肝癌(HCC)与局灶性结节增生(FNH)中的应用及敏感性、特异性分析。方法 选取2016年1月至2017年1月与我院就诊高度怀疑HCC的56例患者及高度怀疑FNH的45例患者作为可研究对象。所有患者均接受64层螺旋CT平扫及增强扫描,并与术后病理证实结果比较,分析螺旋CT对HCC、FNH早期诊断的敏感性与特异性,并对比二者在CT增强扫描时不同能量水平下的对比噪声比(CNR)情况以及能谱定量参数值情况。结果 64层螺旋CT对HCC早期诊断的敏感性为96.23%,特异性为66.67%,准确性为92.86%;对FNH早期诊断的敏感性为92.68%,特异性为75.00%,准确性为86.67%。增强扫描动脉期时HCC、FNH患者CNR均呈明显的下降状态,并且能量越高则CNR越低,HCC与FNH患者的CNR值比较存在显著差异(P<0.05);门脉期FNH患者CNR逐渐降低,而在40 keV时获取最佳CNR,HCC患者则表现为CNR先升后降,80 keV时获取最佳CNR,HCC、FNH患者在80~120keV间的CNR值比较存在显著差异(P<0.05),但在40 keV时比较无显著差异(P>0.05)。结论 64层螺旋CT在早期诊断及鉴别诊断HCC、FNH中具有重要的临床价值,检出效能、敏感性、特异性较高,具有临床应用及推广价值。 相似文献
996.
BackgroundAccurate diagnosis for Arabic speaking critically ill patients suffering from delirium is limited by the need for a valid/reliable translation of a standardized delirium instrument such as the Confusion Assessment Method for the ICU (CAM-ICU).ObjectiveTo determine the validity and reliability of the Arabic version of the CAM-ICU.DesignA prospective cohort study design was used to conduct the current study.SettingsData collection took place in Geriatric, Emergency and Surgical intensive care units.ParticipantsFifty-eight adult patients met the inclusion criteria and participated in the study. Among the participants 22(38%) patients were on mechanical ventilation.MethodsAfter translating the CAM-ICU into Arabic language, the Arabic CAM-ICU was administered by two well-trained critical care nurses and compared with reference standard assessments by delirium experts using the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision (DSM -IV-TR), along with assessment of severity of illness using Sequential Organ Failure Assessment (SOFA). Concurrent validity was assessed by calculating sensitivity, specificity and positive and negative predictive value (PPV and NPV) for the two Arabic CAM-ICU raters, where calculations were based on considering the DSM-IV-TR criterion as the reference standard. The convergent validity of the Arabic CAM-ICU was explored by comparing the Arabic CAM-ICU ratings and the total score of SOFA (severity of illness) and MMSE (cognitive impairment).ResultsA total of 58 ICU patients were included, of whom 27 (47%) were diagnosed with delirium during their ICU stay via DSM-IV criteria. Interrater reliability for the Arabic CAM-ICU, overall and for mechanically ventilated patients assessed using Cohen's kappa (κ) were 0.82 and 1, respectively, p < 0.001. The sensitivities (95% CI) for the two critical care nurses when using the Arabic CAM-ICU compared with the reference standard were 81% (60%–93%) and 85% (65%–95%), respectively, whereas specificity (95% CI) was 81%(62%–92%) for both nurses. High sensitivity and specificity measures were also observed across subgroups; 100% for mechanically ventilated patients, 88% (60%–98%) and 79% (49%–94%) for those aged 65 years or older and 82% (56%–95%) and 75% (43%–93%) for those with SOFA scores at or above the median value.ConclusionsThe Arabic CAM-ICU appeared to be valid and reliable tool for diagnosing delirium. Future investigations may lead to a better understanding of the prevalence, predictors, and consequences of delirium among critically ill Arabic speaking patients. 相似文献
997.
BackgroundWhether the waiting time for radical radiotherapy (WRT) detrimentally impacts nasopharyngeal carcinoma (NPC) prognosis is unclear. We estimated the influence of WRT on overall survival (OS) and disease-specific survival (DSS) of NPC.Patients and methodsPatients were identified from prospectively maintained database. WRT was calculated from histological diagnosis to initiation of radiotherapy (RT). Survival analysis was estimated using Weibull parametric model and propensity score analysis (PSA). Recursive partitioning analysis (RPA) identified optimal WRT threshold via conditional inference trees to estimate the greatest survival differences based on randomly selected training and validation sets, and this process was repeated 1000 times to ensure threshold robustness. Sensitivity analysis estimated effects of potential unmeasured confounders.ResultsA total of 9896 patients were included. In multivariate analysis, WRT of 31–60°d, of 61–90°d and of greater than 90°d independently increased mortality risk compared to less than 30°d. Upon RPA, ranges of 30–35°d with the peak of 30°d were confirmed with 89% of simulations validating optimal thresholds. In threshold-based groups, adjusted hazard ratios (HRs) for WRT of greater than 30°d by both Weibull model and PSA were significantly higher than for WRT of less than 30°d [OS: HR = 1.13, 95% confidence interval (CI) 1.04–1.23, P = 0.003; DSS: HR = 1.15, 95% CI 1.05–1.26, P = 0.002]. Sensitivity analysis revealed robustness of results.ConclusionsWRT independently affects survival. Increasing WRT beyond 30°d was most consistently detrimental to survival. WRT of NPC should be as short as reasonably achievable (ASARA). 相似文献
998.
999.
目的 对全球X线摄影技术运用于乳腺癌筛查的准确性研究进行Meta分析。方法 在Medline、Embase、Cochrane和中国学术期刊网全文数据库(CNKI)文献库中,通过疾病名称、筛查干预、结果指标等关键词整合进行检索。截至2015年6月4日,共检索获得1 167篇文献。根据纳入和排除标准筛选,主要摘录筛查试验中的真阳性、假阳性、假阴性、真阴性的“四格表”数据。采用QUADAS量表进行文献质量评价。利用综合受试者工作特征(SROC)分析方法判断研究间的阈值效应并计算曲线下面积(AUC),采用双变量混合效应模型对X线摄影技术在所有人群和乳腺致密的亚组人群中筛查的灵敏度及特异度进行Meta分析;对样本量大于10万的亚组进行敏感性分析。利用Q检验和I2统计量分析文献异质性,以漏斗图和线性回归方法检验发表偏倚。结果 最终纳入文献48篇(欧洲地区及美国38篇、亚洲地区8篇、大洋洲地区2篇),总样本量为8 551 873例,筛查开展时间为1975-2013年,对象起止筛查年龄大部分在40~75岁。分析得出,X线摄影技术用于乳腺癌筛查的AUC为0.95(95% CI:0.93~0.97),总体灵敏度为0.81(95% CI:0.77~0.84),总体特异度为0.96(95% CI:0.94~0.96),敏感性分析提示该结果稳定。其中对乳腺致密人群的亚组分析显示,X线摄影技术的合并灵敏度和特异度分别为0.74(95% CI:0.61~0.83)和0.93(95% CI:0.89~0.96)。漏斗图和线性回归结果显示纳入研究不存在发表偏倚。结论 X线摄影作为乳腺癌筛查技术具有较高灵敏度和特异度,但对乳腺致密女性的筛查准确性降低。 相似文献
1000.
ObjectivesThe objective of this study was to evaluate the performance of goodness-of-fit testing to detect relevant violations of the assumptions underlying the criticized “standard” two-class latent class model. Often used to obtain sensitivity and specificity estimates for diagnostic tests in the absence of a gold reference standard, this model relies on assuming that diagnostic test errors are independent. When this assumption is violated, accuracy estimates may be biased: goodness-of-fit testing is often used to evaluate the assumption and prevent bias.Study Design and SettingWe investigate the performance of goodness-of-fit testing by Monte Carlo simulation. The simulation scenarios are based on three empirical examples.ResultsGoodness-of-fit tests lack power to detect relevant misfit of the standard two-class latent class model at sample sizes that are typically found in empirical diagnostic studies. The goodness-of-fit tests that are based on asymptotic theory are not robust to the sparseness of data. A parametric bootstrap procedure improves the evaluation of goodness of fit in the case of sparse data.ConclusionOur simulation study suggests that relevant violation of the local independence assumption underlying the standard two-class latent class model may remain undetected in empirical diagnostic studies, potentially leading to biased estimates of sensitivity and specificity. 相似文献