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  • 文章类型: Journal Article
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  • 文章类型: Journal Article
    测试化学污染物的准确性需要使用符合质量文献和标准中概述的验证标准的测试平台。这项研究探讨了由合格的分析师使用美国农业部-联邦谷物检验局批准的用于测量玉米中伏马菌素的试剂盒测量的商业现场数据的应用,以增强方法验证程序。来自七个谷物检测机构的分析师在美国农业部的官方抽样中获得了资格,样品制备,以及使用CharmLF-FUMQ-WETS5的测试方法。使用UPLC-MS-MS在德克萨斯州化学家办公室(OTSC)实验室测试了重复样品。使用连续和分类方法对数据进行了四种统计技术。这种方法使研究人员能够探索单个测试或多个比较是否最适合评估现场套件在整个设施中的适用性。毒素水平,和年份。研究得出的结论是,配对t检验和相关性分析可对套件性能进行快速而有意义的评估。样品在正确的箱中的正确放置(违规与非违规)与市场力量和法规遵从性很好地一致。这项研究的结果也提供了一个有用的工具来评估所有田间试剂盒在收获季节和随后几年的性能。本研究中提出的统计技术的组合是评估霉菌毒素现场测试套件适用性的重要工具,并且代表了旨在保护饲料和食品供应的持续改进质量系统过程中的关键步骤。
    Testing accuracy of a chemical contaminant requires use of a testing platform that conforms to validation criteria outlined in quality literature and standards. This study explores the application of commercial field data measured by qualified analysts using a United States Department of Agriculture - Federal Grain Inspection Service approved kit for measuring fumonisin in maize to augment method validation procedures. Analysts from seven grain testing facilities were qualified in official USDA sampling, sample preparation, and testing methodology using the Charm LF-FUMQ-WETS5. A duplicate sample was tested in the Office of the Texas State Chemist (OTSC) laboratory using UPLC-MS-MS. Data were subject to four statistical techniques using continuous and categorical methodology. This approach enabled researchers to explore if a single test or multiple comparisons were best suited to assess a field kit\'s fitness for purpose across facility, toxin level, and year. The study concluded that a paired t-test and correlation analysis provided a quick and meaningful evaluation of kit performance. The correct placement of samples within the correct bin (violative versus non-violative) aligns well with market forces and regulatory compliance. The results of this study also provide a useful tool to assess all field kits\' performance at the beginning of the harvest season and subsequent years. The combination of statistical techniques presented in this research is an important tool in assessing mycotoxin field test kits fitness for purpose and represents a key step in a continuous improvement-quality systems process meant to protect the feed and food supply.
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  • 文章类型: Journal Article
    背景:旨在保护参与临床研究的儿童的法规通常会限制开发特定年龄疗法和药物剂量所需的研究数据的可用性。关于儿童如何参与临床研究的数据很少,缺乏调查接受强化医疗的幼儿的研究。
    方法:采用半结构化访谈和DISCO-RC问卷的混合方法来探讨幼儿及其父母在肾移植过程中参与临床研究的经验。
    结果:对9名儿童及其父母进行了访谈。儿童肾移植的中位年龄为4岁(IQR4,7);访谈年龄为7岁(IQR6,9)。访谈的主题内容分析显示,大多数儿童不知道参加过一项研究。孩子和他们的父母经常不知道程序是标准护理还是研究相关。归因于研究参与的额外负担从根本没有变化到与强化医学治疗相结合的沉重。积极的经验包括善良的医疗保健专业人员,有效的分心技术,教育方面,有助于科学和额外的检查。大多数报道的负面经历是相互冲突的沟通,花很多时间在医院,缺失学校和次优规划。静脉穿刺对所有孩子都有压力,而其他程序的不适感各不相同。
    结论:儿科临床研究设计应侧重于研究过程中的教育和乐趣,聪明的规划,一致的沟通,临床和研究团队之间的密切合作和年龄适当的分心技术。
    BACKGROUND: Regulations designed to protect children participating in clinical research often restrict the availability of research data necessary for the development of age-specific therapies and drug dosing. Few data exist on how children experience participation in clinical research, and studies investigating young children undergoing an intensive medical treatment are lacking.
    METHODS: Mixed methods with semi-structured interviews and DISCO-RC questionnaires were used to explore young children\'s and their parents\' experiences in clinical research participation during a kidney transplantation trajectory.
    RESULTS: Nine children and their parents were interviewed. Children\'s median age at kidney transplantation was 4 years (IQR 4,7); age at interview was 7 years (IQR 6,9). Thematic content analysis of interviews revealed that most children were unaware of having participated in a study. Both children and their parents frequently were unaware whether procedures were standard care or research related. The additional burden attributed to study participation varied from not at all to heavy in combination with intensive medical treatment. Positive experiences included kind healthcare professionals, effective distraction techniques, educational aspects, contributing to science and extra check-ups. Most reported negative experiences were conflicting communication, spending much time in the hospital, missing school and suboptimal planning. Venous puncture was stressful for all children, whereas the discomfort of other procedures varied.
    CONCLUSIONS: Pediatric clinical research design should focus on education and fun during research procedures, smart planning, consistent communication, close collaboration between clinical and research team and age appropriate distraction techniques.
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  • 文章类型: Journal Article
    许多临床前研究的目的是确定实验性干预是否通过特定机制影响结果。但是通常使用的分析方法和推理逻辑无法回答这个问题,导致关于因果关系的错误结论,这可以是高度可再现的。因果中介分析可以直接测试假设的机制是否部分或完全负责治疗对结果的影响。这种分析可以用现代统计软件容易地实现。我们展示了中介分析如何区分使用标准分析时无法区分的三种不同的因果关系。
    The purpose of many preclinical studies is to determine whether an experimental intervention affects an outcome through a particular mechanism, but the analytical methods and inferential logic typically used cannot answer this question, leading to erroneous conclusions about causal relationships, which can be highly reproducible. A causal mediation analysis can directly test whether a hypothesised mechanism is partly or completely responsible for a treatment\'s effect on an outcome. Such an analysis can be easily implemented with modern statistical software. We show how a mediation analysis can distinguish between three different causal relationships that are indistinguishable when using a standard analysis.
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  • 文章类型: Journal Article
    目的:测量非小细胞肺癌(NSCLC)患者的动态对比增强磁共振成像(DCE-MRI)生物标志物的可重复性。使用这些统计数据来识别哪些个体靶病变显示出早期生物学反应。
    方法:单中心,2015年9月至2017年4月进行了前瞻性DCE-MRI研究。NSCLC患者在标准治疗放疗前进行扫描,以评估生物标志物的可重复性,并在治疗后两周进行扫描,以评估生物反应。体积转移常数(Ktrans),在每个时间点测量血管外细胞外空间体积分数(ve)和血浆体积分数(vp)以及肿瘤体积。使用受试者内变异系数(wCV)和重复性系数(RC)评估重复性。使用混合效应模型估计队列治疗对生物标志物的影响。RC一致性极限揭示了哪些个体目标病变的变化超出了生物标志物每日变化的预期。
    结果:14名患者(平均年龄,67岁+/-12,8名男性)有22个可评估的病变(12个原发性肿瘤,8个淋巴结转移,2个远处转移)。除vp外,所有生物标志物的wCV(在8/14患者中)在9.16%至17.02%之间,为42.44%。队列水平变化对于Ktrans和ve(p<0.001)和肿瘤体积(p=0.002)是显著的。Ktrans和肿瘤体积始终显示出最大数量的个体病变,显示出生物学反应。在区别上,尽管有队列水平的变化,但没有单个病变的ve发生真正的变化.
    结论:识别个体早期生物反应者提供了来自传统队列队列水平统计的额外信息,帮助优先考虑哪些参数最好用于未来的研究。
    结论:动态对比增强磁共振成像生物标志物Ktrans和肿瘤体积是可重复的,并在队列和个体病变水平上检测早期治疗引起的变化。支持其在进一步评估放射治疗和靶向治疗中的使用。
    结论:很少有文献研究报告定量成像生物标志物的精确性,通过测量重复性或再现性。肺癌肿瘤微环境的几种DCE-MRI生物标志物是高度可重复的。重复性系数测量能够对治疗的早期生物学反应进行病变特异性评估,改进常规评估。
    OBJECTIVE: To measure dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) biomarker repeatability in patients with non-small cell lung cancer (NSCLC). To use these statistics to identify which individual target lesions show early biological response.
    METHODS: A single-centre, prospective DCE-MRI study was performed between September 2015 and April 2017. Patients with NSCLC were scanned before standard-of-care radiotherapy to evaluate biomarker repeatability and two weeks into therapy to evaluate biological response. Volume transfer constant (Ktrans), extravascular extracellular space volume fraction (ve) and plasma volume fraction (vp) were measured at each timepoint along with tumour volume. Repeatability was assessed using a within-subject coefficient of variation (wCV) and repeatability coefficient (RC). Cohort treatment effects on biomarkers were estimated using mixed-effects models. RC limits of agreement revealed which individual target lesions changed beyond that expected with biomarker daily variation.
    RESULTS: Fourteen patients (mean age, 67 years +/- 12, 8 men) had 22 evaluable lesions (12 primary tumours, 8 nodal metastases, 2 distant metastases). The wCV (in 8/14 patients) was between 9.16% to 17.02% for all biomarkers except for vp, which was 42.44%. Cohort-level changes were significant for Ktrans and ve (p < 0.001) and tumour volume (p = 0.002). Ktrans and tumour volume consistently showed the greatest number of individual lesions showing biological response. In distinction, no individual lesions had a real change in ve despite the cohort-level change.
    CONCLUSIONS: Identifying individual early biological responders provided additional information to that derived from conventional cohort cohort-level statistics, helping to prioritise which parameters would be best taken forward into future studies.
    CONCLUSIONS: Dynamic contrast-enhanced magnetic resonance imaging biomarkers Ktrans and tumour volume are repeatable and detect early treatment-induced changes at both cohort and individual lesion levels, supporting their use in further evaluation of radiotherapy and targeted therapeutics.
    CONCLUSIONS: Few literature studies report quantitative imaging biomarker precision, by measuring repeatability or reproducibility. Several DCE-MRI biomarkers of lung cancer tumour microenvironment were highly repeatable. Repeatability coefficient measurements enabled lesion-specific evaluation of early biological response to therapy, improving conventional assessment.
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  • 文章类型: Journal Article
    背景弧菌属包括波罗的海地区(BSR)中存在的几种细菌物种,已知会导致人类感染。目的对1994年至2021年BSR中弧菌引起的感染进行全面的回顾性分析,重点是四大弧菌-溶藻弧菌,非O1/O139霍乱弧菌,副溶血性弧菌和创伤弧菌-在八个欧洲国家(丹麦,爱沙尼亚,芬兰,德国,拉脱维亚,立陶宛,波兰和瑞典)毗邻波罗的海。方法我们的分析包括感染数据,从国家卫生机构收到的或从科学文献和在线数据库中提取的沿海水域弧菌物种分布和环境数据。进行了冗余分析,以确定几个独立变量的潜在影响,例如海面温度,盐度,指定沿海海滩的数量和年份,弧菌感染率。结果对于进行监测的BSR国家,随着时间的推移,我们观察到该地区弧菌感染总数(n=1,553)呈指数增长。在瑞典和德国,弧菌总数。溶藻弧菌和副溶血性弧菌引起的感染与海表温度升高呈正相关。盐度成为弧菌属的关键驱动因素。分布和丰度。此外,我们提出的统计模型揭示了立陶宛和波兰的12到20个未报告病例,分别,没有监控的国家。结论各国在弧菌监测和监测方面存在差异,强调需要对这些病原体进行全面监测,以保护人类健康,特别是在气候变化的背景下。
    BackgroundThe Vibrio genus comprises several bacterial species present in the Baltic Sea region (BSR), which are known to cause human infections.AimTo provide a comprehensive retrospective analysis of Vibrio-induced infections in the BSR from 1994 to 2021, focusing on the \'big four\' Vibrio species - V. alginolyticus, V. cholerae non-O1/O139, V. parahaemolyticus and V. vulnificus - in eight European countries (Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland and Sweden) bordering the Baltic Sea.MethodsOur analysis includes data on infections, Vibrio species distribution in coastal waters and environmental data received from national health agencies or extracted from scientific literature and online databases. A redundancy analysis was performed to determine the potential impact of several independent variables, such as sea surface temperature, salinity, the number of designated coastal beaches and year, on the Vibrio infection rate.ResultsFor BSR countries conducting surveillance, we observed an exponential increase in total Vibrio infections (n = 1,553) across the region over time. In Sweden and Germany, total numbers of Vibrio spp. and infections caused by V. alginolyticus and V. parahaemolyticus positively correlate with increasing sea surface temperature. Salinity emerged as a critical driver of Vibrio spp. distribution and abundance. Furthermore, our proposed statistical model reveals 12 to 20 unreported cases in Lithuania and Poland, respectively, countries with no surveillance.ConclusionsThere are discrepancies in Vibrio surveillance and monitoring among countries, emphasising the need for comprehensive monitoring programmes of these pathogens to protect human health, particularly in the context of climate change.
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  • 文章类型: English Abstract
    UNASSIGNED: Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that can affect multiple organs and body systems.
    UNASSIGNED: To describe the sociodemographic, clinical, and biochemical characteristics of the Lupus-IMMS-Mexico (LUPUS-IMMex) patient cohort from a tertiary-level center.
    UNASSIGNED: Observational descriptive study of 160 patients with diagnosis of SLE belonging to the aforementioned cohort. Various variables were analyzed at the time of diagnosis. For quantitative variables, normality tests were applied, followed by measures of central tendency and dispersion according to their distribution. For categorical variables, frequencies and percentages were calculated.
    UNASSIGNED: 81.87% of the patients were female, with a median age at diagnosis of 28 years. 18.12% had a family history of SLE, and concurrently with SLE, 32.50% had hypertension, and 11.25% had antiphospholipid syndrome. The most common clinical manifestation was joint involvement (68.12%), renal (49.37%) and hematological (43.75%) manifestations.
    UNASSIGNED: SLE affects millions globally. Lack of awareness leads to delayed diagnoses, suboptimal management, and diminished quality of life. After analyzing 160 patients with SLE, their clinical, socioeconomic, and therapeutic characteristics are largely like other cohorts, with differences attributable to ethnic and geographical influences. Informing patients about SLE and providing reliable resources are essential for self-care. Awareness promotes research, therapies, and enhances medical care and the lives of patients globally.
    UNASSIGNED: el lupus eritematoso sistémico (LES) es una enfermedad autoinmunitaria crónica que puede afectar a múltiples órganos y sistemas del cuerpo.
    UNASSIGNED: describir las características sociodemográficas, clínicas y bioquímicas de la cohorte de pacientes Lupus-IMMS-México (LUPUS-IMMex) de un hospital de tercer nivel.
    UNASSIGNED: estudio descriptivo observacional de 160 pacientes con diagnóstico de LES de la cohorte mencionada. Se analizaron diversas variables al momento del diagnóstico. Para variables cuantitativas se aplicaron pruebas de normalidad y posteriormente medidas de tendencia central y dispersión de acuerdo con su distribución. Para variables categóricas se calcularon frecuencias y porcentajes.
    UNASSIGNED: 81.87% de los pacientes fueron del sexo femenino, con mediana de edad al diagnóstico de 28 años. El 18.12% tenían antecedentes familiares de LES y concomitante al LES, hipertensión (32.50%) y síndromes antifosfolípidos (11.25%). Las afecciones clínicas más frecuentes fueron la articular (68.12%), la renal (49.37%) y la hematológica (43.75%).
    UNASSIGNED: el LES afecta a millones de personas globalmente. La falta de conciencia lleva a diagnósticos tardíos, manejo deficiente y baja calidad de vida. Tras analizar 160 pacientes con LES, sus características clínicas, socioeconómicas y terapéuticas son mayormente similares a otras cohortes, con diferencias atribuibles a influencias étnicas y geográficas. Informar a los pacientes sobre el LES y brindar recursos confiables es esencial para el autocuidado. La sensibilización fomenta la investigación, las terapias y mejora la atención médica y la vida de pacientes a nivel global.
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  • 文章类型: Journal Article
    背景:来自单细胞RNA测序数据的谱系追踪和轨迹推断在揭示驱动发育和疾病的遗传程序方面具有巨大潜力。单细胞数据集被认为提供了关于组织的不同细胞结构的无偏视图。采样偏差,然而,可以使单细胞数据集偏离它们要代表的细胞组成。
    结果:我们展示了一种新形式的抽样偏差,由与不断增长的重复采样有关的统计现象引起的,异质种群。细胞的相对生长速率影响它们将在多个时间点观察到的克隆中取样的概率。我们通过模拟研究和对T细胞发育的实时过程的分析来支持我们的概率推导。我们发现这种偏差会影响命运概率预测,我们探索如何开发对这种偏差具有鲁棒性的轨迹推理方法。
    背景:用于模拟数据集和创建本手稿中的图形的源代码可以在https://github.com/rbonhamcarter/simulate-clones的python中免费获得。LineageOT方法扩展的python实现可在https://github.com/rbonhamcarter/LineageOT/tree/multi-time-clone上免费获得。
    背景:补充数据可在Bioinformation在线获得。
    BACKGROUND: Lineage tracing and trajectory inference from single-cell RNA-sequencing data hold tremendous potential for uncovering the genetic programs driving development and disease. Single cell datasets are thought to provide an unbiased view on the diverse cellular architecture of tissues. Sampling bias, however, can skew single cell datasets away from the cellular composition they are meant to represent.
    RESULTS: We demonstrate a novel form of sampling bias, caused by a statistical phenomenon related to repeated sampling from a growing, heterogeneous population. Relative growth rates of cells influence the probability that they will be sampled in clones observed across multiple time points. We support our probabilistic derivations with a simulation study and an analysis of a real time-course of T-cell development. We find that this bias can impact fate probability predictions, and we explore how to develop trajectory inference methods which are robust to this bias.
    METHODS: Source code for the simulated datasets and to create the figures in this manuscript is freely available in python at https://github.com/rbonhamcarter/simulate-clones. A python implementation of the extension of the LineageOT method is freely available at https://github.com/rbonhamcarter/LineageOT/tree/multi-time-clones.
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  • 文章类型: Journal Article
    在实验动物设施中,定期进行健康监测对于确定特定病原体的存在与否至关重要。一种常见的监测方法是使用前哨动物,它们定期暴露于被监测的笼子里的生物材料。在某一点上,其中一些前哨动物接受了病原体测试。本文讨论了设计有效的采样方案以满足所需的质量标准。它解决了诸如所需哨兵动物数量等问题,采样生物材料的频率,根据设施设置选择笼子,以及前哨动物试验的最佳频率和数量。虽然现有的设计公式可用于简单的随机抽样,据我们所知,没有定量建议使用前哨动物。本文提出了一种基于蒙特卡罗模拟的方法来解决这个问题。我们的算法已在http://nolan的可公开访问的网页中实现。cnb.csic.es/sentinelcagesmanager。
    Regular health monitoring is crucial in laboratory animal facilities to determine the presence or absence of specific pathogens. One common approach to monitoring involves the use of sentinel animals, which are periodically exposed to biological material from the cages being monitored. At a certain point, some of these sentinel animals are tested for pathogens. This article discusses designing an effective sampling scheme to meet desired quality standards. It addresses questions such as the number of sentinel animals required, the frequency of sampling biological material, the selection of cages based on facility set-up, and the optimal frequency and quantity of sentinel animal tests. While existing design formulas are available for simple random sampling, no quantitative recommendation exists for using sentinel animals to the best of our knowledge. We propose a Monte Carlo simulation-based approach in this article to address this. Our algorithm has been implemented in a publicly accessible web page at http://nolan.cnb.csic.es/sentinelcagesmanager.
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  • 文章类型: Journal Article
    目的:这项研究的目的是评估基于同位素重新网格和统计形状分析(SSA)的组合方法的准确性,以捕获改变和完整的前磨牙的关键解剖特征。此外,该研究比较了四种机器学习(ML)算法在识别或模拟牙齿改变方面的能力。
    方法:分析了多中心数据库中的113个前磨牙表面。这些表面使用同位素重新划分方法进行处理,其次是SSA。计算初始和重新网格的STL文件之间的平均欧几里德距离,以评估解剖标志定位的偏差。从每颗牙齿中提取了七个解剖特征,并探讨了它们与形态模式和形态特征的相关性。四种ML算法,通过三次交叉验证进行验证,评估了他们对牙齿类型和改变进行分类的能力。此外,对20颗完整的牙齿进行了改造,然后进行了重建,以验证该方法的准确性。
    结果:前五种模式封装了76.1%的总形状变异性,平均地标定位偏差为10.4µm(±6.4)。在形状模式和特定的形态特征之间发现了显着的相关性。最佳ML算法显示出较高的准确性(>83%)和精度(>86%)。对完整牙齿的模拟显示,解剖特征的差异低于3%。
    结论:同位素重新啮合与SSA的组合在捕获牙齿的关键解剖特征方面显示出良好的可靠性。
    结论:ML算法的令人鼓舞的表现为支持从业者诊断和规划牙齿改变患者的治疗提供了一个有希望的方向。最终改善预防性护理。
    OBJECTIVE: The aim of this study was to evaluate the accuracy of a combined approach based on an isotopological remeshing and statistical shape analysis (SSA) to capture key anatomical features of altered and intact premolars. Additionally, the study compares the capabilities of four Machine Learning (ML) algorithms in identifying or simulating tooth alterations.
    METHODS: 113 premolar surfaces from a multicenter database were analyzed. These surfaces were processed using an isotopological remeshing method, followed by a SSA. Mean Euclidean distances between the initial and remeshed STL files were calculated to assess deviation in anatomical landmark positioning. Seven anatomical features were extracted from each tooth, and their correlations with shape modes and morphological characteristics were explored. Four ML algorithms, validated through three-fold cross-validation, were assessed for their ability to classify tooth types and alterations. Additionally, twenty intact teeth were altered and then reconstructed to verify the method\'s accuracy.
    RESULTS: The first five modes encapsulated 76.1% of the total shape variability, with a mean landmark positioning deviation of 10.4 µm (±6.4). Significant correlations were found between shape modes and specific morphological features. The optimal ML algorithms demonstrated high accuracy (>83%) and precision (>86%). Simulations on intact teeth showed discrepancies in anatomical features below 3%.
    CONCLUSIONS: The combination of an isotopological remeshing with SSA showed good reliability in capturing key anatomical features of the tooth.
    CONCLUSIONS: The encouraging performance of ML algorithms suggests a promising direction for supporting practitioners in diagnosing and planning treatments for patients with altered teeth, ultimately improving preventive care.
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