Stratification

分层
  • 文章类型: Journal Article
    背景:运动困难在许多地方都很常见,但不是全部,自闭症患者。这些困难可能与其他问题同时发生,比如语言的延迟,知识分子,和适应性功能。支撑这种困难的生物机制不太清楚。在携带高度渗透的罕见基因突变的个体中,运动技能差往往更常见。这种机制可能具有改变神经生理兴奋-抑制平衡的下游后果,并导致行为运动噪声增强。
    方法:这项研究结合了自闭症患者的公开数据集和内部数据集(n=156),典型的发展(TD,n=149),和发育协调障碍(DCD,n=23)儿童(3-16岁)。根据《儿童运动评估电池》第2版测量的运动能力模式,确定了自闭症运动亚型。基于稳定性的相对聚类验证用于识别自闭症运动亚型并评估保留数据中的泛化准确性。自闭症电机亚型进行了电机噪声的差异测试,操作为在简单的触地任务中记录的重复运动运动轨迹之间的不相似程度。
    结果:可以检测到相对的“高”(n=87)与“低”(n=69)自闭症运动亚型,并且在保留数据中以89%的准确率进行推广。相对“低”亚型的一般智力较低,在独立行走年龄较大,但在第一个单词的年龄或自闭症特征或症状学上没有差异。与“高”(科恩的d=0.77)或TD儿童(科恩的d=0.85)相比,“低”亚型的电机噪声要高得多,但自闭症儿童和TD儿童之间相似(科恩的d=0.08)。在到达动作的前馈阶段,\'低\'亚型中增强的电动机噪声也最为明显。
    结论:这项工作的样本量有限。未来在较大样本中的工作以及独立复制非常重要。仅在一个特定的电机任务上测量电机噪声。因此,需要对许多其他电机任务中的电机噪声进行更全面的评估。
    结论:自闭症可以分为至少两种离散的运动亚型,其特征是运动噪声水平不同。这表明自闭症运动亚型可能受到不同生物学机制的支持。
    BACKGROUND: Motor difficulties are common in many, but not all, autistic individuals. These difficulties can co-occur with other problems, such as delays in language, intellectual, and adaptive functioning. Biological mechanisms underpinning such difficulties are less well understood. Poor motor skills tend to be more common in individuals carrying highly penetrant rare genetic mutations. Such mechanisms may have downstream consequences of altering neurophysiological excitation-inhibition balance and lead to enhanced behavioral motor noise.
    METHODS: This study combined publicly available and in-house datasets of autistic (n = 156), typically-developing (TD, n = 149), and developmental coordination disorder (DCD, n = 23) children (age 3-16 years). Autism motor subtypes were identified based on patterns of motor abilities measured from the Movement Assessment Battery for Children 2nd edition. Stability-based relative clustering validation was used to identify autism motor subtypes and evaluate generalization accuracy in held-out data. Autism motor subtypes were tested for differences in motor noise, operationalized as the degree of dissimilarity between repeated motor kinematic trajectories recorded during a simple reach-to-drop task.
    RESULTS: Relatively \'high\' (n = 87) versus \'low\' (n = 69) autism motor subtypes could be detected and which generalize with 89% accuracy in held-out data. The relatively \'low\' subtype was lower in general intellectual ability and older at age of independent walking, but did not differ in age at first words or autistic traits or symptomatology. Motor noise was considerably higher in the \'low\' subtype compared to \'high\' (Cohen\'s d = 0.77) or TD children (Cohen\'s d = 0.85), but similar between autism \'high\' and TD children (Cohen\'s d = 0.08). Enhanced motor noise in the \'low\' subtype was also most pronounced during the feedforward phase of reaching actions.
    CONCLUSIONS: The sample size of this work is limited. Future work in larger samples along with independent replication is important. Motor noise was measured only on one specific motor task. Thus, a more comprehensive assessment of motor noise on many other motor tasks is needed.
    CONCLUSIONS: Autism can be split into at least two discrete motor subtypes that are characterized by differing levels of motor noise. This suggests that autism motor subtypes may be underpinned by different biological mechanisms.
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  • 文章类型: Journal Article
    背景:心房颤动(AF)是全球最常见的心律失常,与较高的死亡率和发病率风险有关。预测房颤和房颤相关并发症,临床风险评分通常采用,但是它们的预测准确性通常是有限的,考虑到房颤患者固有的复杂性和异质性。通过将房颤的不同表现分类为连贯且可管理的临床表型,可以促进制定量身定制的预防和治疗策略。在这项研究中,我们提出了一种基于人工智能(AI)的方法,以在普通和重症监护人群中得出有意义的房颤临床表型。
    方法:我们的方法采用了生成地形图,概率机器学习方法,识别具有相似特征的患者的微集群。然后使用Ward的最小方差方法识别潜在空间中的宏簇区域(临床表型)。我们将其应用于代表普通和重症监护人群的两个大型队列数据库(UK-Biobank和MIMIC-IV)。
    结果:所提出的方法学表明其能够获得有意义的房颤临床表型。因为它的概率基础,它可以增强患者分层的鲁棒性。它还产生了复杂的高维数据的可解释可视化,加强对衍生表型及其关键特征的理解。使用我们的方法,我们在不同患者人群中鉴定并表征了房颤的临床表型.
    结论:我们的方法对噪声是稳健的,可以发现隐藏的模式和子组,并且可以阐明更具体的患者概况,有助于更可靠的患者分层,这可以促进针对每种表型的预防和治疗方案的定制。它还可以应用于其他数据集以得出其他病症的临床上有意义的表型。
    背景:本研究由DECIPHER项目(LJMUQR-PSF)和欧盟项目TARGET(10113624)资助。
    BACKGROUND: Atrial fibrillation (AF) is the most common heart arrhythmia worldwide and is linked to a higher risk of mortality and morbidity. To predict AF and AF-related complications, clinical risk scores are commonly employed, but their predictive accuracy is generally limited, given the inherent complexity and heterogeneity of patients with AF. By classifying different presentations of AF into coherent and manageable clinical phenotypes, the development of tailored prevention and treatment strategies can be facilitated. In this study, we propose an artificial intelligence (AI)-based methodology to derive meaningful clinical phenotypes of AF in the general and critical care populations.
    METHODS: Our approach employs generative topographic mapping, a probabilistic machine learning method, to identify micro-clusters of patients with similar characteristics. It then identifies macro-cluster regions (clinical phenotypes) in the latent space using Ward\'s minimum variance method. We applied it to two large cohort databases (UK-Biobank and MIMIC-IV) representing general and critical care populations.
    RESULTS: The proposed methodology showed its ability to derive meaningful clinical phenotypes of AF. Because of its probabilistic foundations, it can enhance the robustness of patient stratification. It also produced interpretable visualisation of complex high-dimensional data, enhancing understanding of the derived phenotypes and their key characteristics. Using our methodology, we identified and characterised clinical phenotypes of AF across diverse patient populations.
    CONCLUSIONS: Our methodology is robust to noise, can uncover hidden patterns and subgroups, and can elucidate more specific patient profiles, contributing to more robust patient stratification, which could facilitate the tailoring of prevention and treatment programs specific to each phenotype. It can also be applied to other datasets to derive clinically meaningful phenotypes of other conditions.
    BACKGROUND: This study was funded by the DECIPHER project (LJMU QR-PSF) and the EU project TARGET (10113624).
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  • 文章类型: Journal Article
    背景:在亨廷顿病临床试验中,招募和分层方法主要依赖于遗传负荷,认知和运动评估得分。他们不太关注体内脑成像标记,在临床诊断之前很好地反映了神经病理学。机器学习方法提供了一定程度的复杂性,可以通过利用来自大型数据集的多模态生物标志物来显着改善预后和分层。这种专门针对HD基因扩增载体定制的模型可以进一步增强分层过程的功效。
    目的:改善亨廷顿病患者的临床试验分层。
    方法:我们使用了先前发表的队列中451名患有亨廷顿病的基因阳性个体(包括预见性和诊断性)的数据(PREDICT,TRACK,TrackON,和图像)。我们将全脑分割应用于纵向脑部扫描,并测量侧脑室扩大的速度,超过3年,它被用作我们的预后随机森林回归模型的目标变量。模型在基线时对特征的各种组合进行了训练,包括遗传负荷,认知和运动评估评分生物标志物,以及脑成像衍生的特征。此外,我们建立了一个简化的分层模型,根据预期的心室扩大率将个体分为两个同质组(低危和高危).
    结果:通过整合脑成像特征和遗传负荷,预后模型的预测准确性大大提高,认知和运动生物标志物:交叉验证的平均绝对误差减少24%,产生530mm3/年的误差。分层模型在区分中等和快速进展者方面的交叉验证准确性为81%(精度=83%,召回=80%)。
    结论:这项研究验证了机器学习在根据心室扩大率区分低危和高危个体方面的有效性。这些模型是使用HD个体的特征进行专门训练的,这提供了更多的疾病特异性,简化,与依赖从健康对照组中提取的特征相比,预后富集的准确方法,正如以前的研究所做的那样。所提出的方法有可能通过以下方式提高临床效用:i)使更有针对性地招募个人进行临床试验,ii)改善对个人的事后评估,和iii)最终通过个性化治疗选择为个人带来更好的结果。
    BACKGROUND: In Huntington\'s disease clinical trials, recruitment and stratification approaches primarily rely on genetic load, cognitive and motor assessment scores. They focus less on in vivo brain imaging markers, which reflect neuropathology well before clinical diagnosis. Machine learning methods offer a degree of sophistication which could significantly improve prognosis and stratification by leveraging multimodal biomarkers from large datasets. Such models specifically tailored to HD gene expansion carriers could further enhance the efficacy of the stratification process.
    OBJECTIVE: To improve stratification of Huntington\'s disease individuals for clinical trials.
    METHODS: We used data from 451 gene positive individuals with Huntington\'s disease (both premanifest and diagnosed) from previously published cohorts (PREDICT, TRACK, TrackON, and IMAGE). We applied whole-brain parcellation to longitudinal brain scans and measured the rate of lateral ventricular enlargement, over 3 years, which was used as the target variable for our prognostic random forest regression models. The models were trained on various combinations of features at baseline, including genetic load, cognitive and motor assessment score biomarkers, as well as brain imaging-derived features. Furthermore, a simplified stratification model was developed to classify individuals into two homogenous groups (low risk and high risk) based on their anticipated rate of ventricular enlargement.
    RESULTS: The predictive accuracy of the prognostic models substantially improved by integrating brain imaging features alongside genetic load, cognitive and motor biomarkers: a 24 % reduction in the cross-validated mean absolute error, yielding an error of 530 mm3/year. The stratification model had a cross-validated accuracy of 81 % in differentiating between moderate and fast progressors (precision = 83 %, recall = 80 %).
    CONCLUSIONS: This study validated the effectiveness of machine learning in differentiating between low- and high-risk individuals based on the rate of ventricular enlargement. The models were exclusively trained using features from HD individuals, which offers a more disease-specific, simplified, and accurate approach for prognostic enrichment compared to relying on features extracted from healthy control groups, as done in previous studies. The proposed method has the potential to enhance clinical utility by: i) enabling more targeted recruitment of individuals for clinical trials, ii) improving post-hoc evaluation of individuals, and iii) ultimately leading to better outcomes for individuals through personalized treatment selection.
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  • 文章类型: Journal Article
    与失业相关的不良生活过程事件会对个人未来的劳动力市场前景产生负面影响。未授权状态,以及随后未经授权的就业,可以类似地操作,即使移民改变了法律地位,也会损害他们的劳动力市场前景。然而,目前尚不清楚与先前未经授权的身份相关的任何持久劣势如何以及为什么会因性别而异。鉴于法律地位和性别重叠影响移徙和分层,这是一个重要的缺点。使用来自全国代表性合法永久居民样本的纵向数据,我们发现与先前暴露于未经授权的状态相关的持久缺点,尤其是女性。相对于从未未经授权的男性,先前接触过未经授权的男性会经历持续的职业劣势。然而,与从未获得过未经授权的女性相比,暴露于未经授权身份的女性随着时间的推移会经历越来越大的职业劣势。人力资本和法律程序有助于解释这种模式。
    Adverse life course events associated with unemployment can negatively affect individuals\' future labor market prospects. Unauthorized status, and subsequent unauthorized employment, may operate similarly, marring immigrants\' labor market prospects even after they change legal status. However, it is unclear how and why any durable disadvantage associated with prior unauthorized status operates differently by gender. This is an important shortcoming given that legal status and gender overlap to influence both migration and stratification. Using longitudinal data from a nationally-representative sample of lawful permanent residents, we find durable disadvantage associated with prior exposure to unauthorized status, especially among women. Men with prior exposure to unauthorized status experience persistent occupational disadvantage over time relative to men who were never unauthorized. However, women with exposure to unauthorized status experience widening occupational disadvantage over time relative to women who were never unauthorized. Human capital and legal processes help to explain this pattern.
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  • 文章类型: Journal Article
    地球上最敌对的海洋栖息地之一是南太平洋环流(SPG)的表面,具有高太阳辐射的特点,营养极度枯竭和生产力低下。在SO-245“UltraPac”巡航通过超贫营养SPG中心期间,通过荧光原位杂交检测到海洋α-蛋白质细菌组AEGEAN169,其相对丰度高达最上层水层总微生物群落的6%,具有两个不同的种群(念珠菌Nemonibacter和Ca。Indimonas).分裂细胞的高频率与高转录水平相结合,这表明这两种进化枝可能具有高度代谢活性。AEGEAN169的比较宏基因组和代谢组学分析显示,与竞争对手SAR11,SAR86,SAR116和Prochloroccocus相比,它们对这种极端环境编码了微妙但独特的代谢适应。两种AEGEAN169进化枝每个预测蛋白的转运蛋白百分比最高(9.5%和10.6%,分别)。特别是,ABC转运蛋白与蛋白视紫红质的高表达和分解代谢途径的检测,建议两种AEGEAN169进化枝的潜在清除生活方式。尽管两个AEGEAN169进化枝可能共享利用膦酸盐作为磷源的基因组潜力,它们的碳和氮代谢途径不同。Ca.Nemonibacter可能使用甘氨酸甜菜碱,而Ca。氨单胞菌可能会分解尿素,肌酸,和狗娘养的。总之,两种进化枝的不同潜在代谢策略表明,两者都很好地适应了资源有限的条件,并与SPG地表水最上层的其他优势微生物进化枝竞争良好。
    One of the most hostile marine habitats on Earth is the surface of the South Pacific Gyre (SPG), characterized by high solar radiation, extreme nutrient depletion, and low productivity. During the SO-245 \"UltraPac\" cruise through the center of the ultra-oligotrophic SPG, the marine alphaproteobacterial group AEGEAN169 was detected by fluorescence in situ hybridization at relative abundances up to 6% of the total microbial community in the uppermost water layer, with two distinct populations (Candidatus Nemonibacter and Ca. Indicimonas). The high frequency of dividing cells combined with high transcript levels suggests that both clades may be highly metabolically active. Comparative metagenomic and metatranscriptomic analyses of AEGEAN169 revealed that they encoded subtle but distinct metabolic adaptions to this extreme environment in comparison to their competitors SAR11, SAR86, SAR116, and Prochlorococcus. Both AEGEAN169 clades had the highest percentage of transporters per predicted proteins (9.5% and 10.6%, respectively). In particular, the high expression of ABC transporters in combination with proteorhodopsins and the catabolic pathways detected suggest a potential scavenging lifestyle for both AEGEAN169 clades. Although both AEGEAN169 clades may share the genomic potential to utilize phosphonates as a phosphorus source, they differ in their metabolic pathways for carbon and nitrogen. Ca. Nemonibacter potentially use glycine-betaine, whereas Ca. Indicimonas may catabolize urea, creatine, and fucose. In conclusion, the different potential metabolic strategies of both clades suggest that both are well adapted to thrive resource-limited conditions and compete well with other dominant microbial clades in the uppermost layers of SPG surface waters.
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  • 文章类型: Journal Article
    微生物群落,其中包括原核生物和原生生物,在水生生态系统中发挥重要作用,影响生态过程。为了了解这些社区,元编码提供了一个强大的工具来评估它们的分类组成和跟踪海洋和淡水环境中的时空动态。虽然海洋生态系统已经被广泛研究,在了解温带湖泊中的真核微生物群落方面存在显著的研究空白。我们的研究通过调查罗希湖(波兰)的自由生活细菌和小型原生群落来解决这一差距,一个不协调的温带湖泊。代谢编码分析显示,细菌和原生群落都表现出不同的季节性模式,不一定由优势类群塑造。此外,机器学习和统计方法确定了每个季节特有的关键扩增子序列变体(ASV)。此外,我们在缺氧性低血中发现了一个独特的群落。我们还表明,塑造所分析群落组成的关键因素是温度,氧和硅的浓度。在气候变化可能影响混合模式并导致长期分层的背景下,了解这些社区结构和潜在因素非常重要。
    Microbial communities, which include prokaryotes and protists, play an important role in aquatic ecosystems and influence ecological processes. To understand these communities, metabarcoding provides a powerful tool to assess their taxonomic composition and track spatio-temporal dynamics in both marine and freshwater environments. While marine ecosystems have been extensively studied, there is a notable research gap in understanding eukaryotic microbial communities in temperate lakes. Our study addresses this gap by investigating the free-living bacteria and small protist communities in Lake Roś (Poland), a dimictic temperate lake. Metabarcoding analysis revealed that both the bacterial and protist communities exhibit distinct seasonal patterns that are not necessarily shaped by dominant taxa. Furthermore, machine learning and statistical methods identified crucial amplicon sequence variants (ASVs) specific to each season. In addition, we identified a distinct community in the anoxic hypolimnion. We have also shown that the key factors shaping the composition of analysed community are temperature, oxygen, and silicon concentration. Understanding these community structures and the underlying factors is important in the context of climate change potentially impacting mixing patterns and leading to prolonged stratification.
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  • 文章类型: Journal Article
    对于类风湿性关节炎(RA),长期的慢性疾病,识别和描述具有可比的目标状态和分子生物标志物的患者亚型至关重要.本研究旨在开发和验证一种新的分型方案,该方案整合了RA外周血基因的基因组尺度转录组学图谱,为分层治疗提供了新的视角。
    我们利用RA外周血单核细胞(PBMC)的独立微阵列数据集。对上调的差异表达基因(DEGs)进行功能富集分析。然后采用无监督聚类分析来鉴定RA外周血基因表达驱动的亚型。我们基于识别的404个上调的DEGs定义了三种不同的聚类亚型。
    子类型A,名为NE驾驶,富含与中性粒细胞活化和对细菌反应相关的途径。亚型B,称为干扰素驱动(IFN驱动),表现出丰富的B细胞,并显示参与IFN信号传导和对病毒的防御反应的转录本的表达增加。在亚型C中,发现了CD8+T细胞的富集,最终将其定义为CD8+T细胞驱动。使用XGBoost机器学习算法对RA亚型方案进行了验证。我们还评估了生物疾病缓解抗风湿药物的治疗效果。
    这些发现为深层分层提供了有价值的见解,能够设计分子诊断,并作为未来RA患者分层治疗的参考。
    UNASSIGNED: For Rheumatoid Arthritis (RA), a long-term chronic illness, it is essential to identify and describe patient subtypes with comparable goal status and molecular biomarkers. This study aims to develop and validate a new subtyping scheme that integrates genome-scale transcriptomic profiles of RA peripheral blood genes, providing a fresh perspective for stratified treatments.
    UNASSIGNED: We utilized independent microarray datasets of RA peripheral blood mononuclear cells (PBMCs). Up-regulated differentially expressed genes (DEGs) were subjected to functional enrichment analysis. Unsupervised cluster analysis was then employed to identify RA peripheral blood gene expression-driven subtypes. We defined three distinct clustering subtypes based on the identified 404 up-regulated DEGs.
    UNASSIGNED: Subtype A, named NE-driving, was enriched in pathways related to neutrophil activation and responses to bacteria. Subtype B, termed interferon-driving (IFN-driving), exhibited abundant B cells and showed increased expression of transcripts involved in IFN signaling and defense responses to viruses. In Subtype C, an enrichment of CD8+ T-cells was found, ultimately defining it as CD8+ T-cells-driving. The RA subtyping scheme was validated using the XGBoost machine learning algorithm. We also evaluated the therapeutic outcomes of biological disease-modifying anti-rheumatic drugs.
    UNASSIGNED: The findings provide valuable insights for deep stratification, enabling the design of molecular diagnosis and serving as a reference for stratified therapy in RA patients in the future.
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  • 文章类型: Journal Article
    背景:患者异质性对个人管理和临床试验设计提出了重大挑战,尤其是复杂的疾病。现有的分类依赖于结果预测分数,可能忽略导致异质性的关键因素,而不一定影响预后。
    方法:为了解决患者异质性,我们开发了ClustALL,同时面临各种临床数据挑战的计算管道,如混合类型,缺少值,和共线性。ClustALL能够无监督地识别患者分层,同时过滤针对群体中的微小变化(基于群体)和算法参数中的有限调整(基于参数)具有鲁棒性的分层。
    结果:应用于急性失代偿期肝硬化患者的欧洲队列(n=766),ClustALL确定了五个稳健的分层,仅使用入院时的数据。所有分层包括肝功能受损的标志物和器官功能障碍或衰竭的数量。其中大多数包括突发性事件。当关注这些分层之一时,患者被分为三组,以典型的临床特征为特征;值得注意的是,3组分层显示了预后价值.在随访期间重新评估患者分层,描绘患者的结果,进一步改善了分层的预后价值。我们在来自拉丁美洲(n=580)的独立前瞻性多中心队列中验证了这些发现。
    结论:通过将ClustALL应用于急性失代偿期肝硬化患者,我们确定了三个患者群.随着时间的推移,这些集群提供了可以指导未来临床试验设计的见解。ClustALL是一种新颖而强大的分层方法,能够解决大多数复杂疾病中患者分层的多重挑战。
    BACKGROUND: Patient heterogeneity poses significant challenges for managing individuals and designing clinical trials, especially in complex diseases. Existing classifications rely on outcome-predicting scores, potentially overlooking crucial elements contributing to heterogeneity without necessarily impacting prognosis.
    METHODS: To address patient heterogeneity, we developed ClustALL, a computational pipeline that simultaneously faces diverse clinical data challenges like mixed types, missing values, and collinearity. ClustALL enables the unsupervised identification of patient stratifications while filtering for stratifications that are robust against minor variations in the population (population-based) and against limited adjustments in the algorithm\'s parameters (parameter-based).
    RESULTS: Applied to a European cohort of patients with acutely decompensated cirrhosis (n = 766), ClustALL identified five robust stratifications, using only data at hospital admission. All stratifications included markers of impaired liver function and number of organ dysfunction or failure, and most included precipitating events. When focusing on one of these stratifications, patients were categorized into three clusters characterized by typical clinical features; notably, the 3-cluster stratification showed a prognostic value. Re-assessment of patient stratification during follow-up delineated patients\' outcomes, with further improvement of the prognostic value of the stratification. We validated these findings in an independent prospective multicentre cohort of patients from Latin America (n = 580).
    CONCLUSIONS: By applying ClustALL to patients with acutely decompensated cirrhosis, we identified three patient clusters. Following these clusters over time offers insights that could guide future clinical trial design. ClustALL is a novel and robust stratification method capable of addressing the multiple challenges of patient stratification in most complex diseases.
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  • 文章类型: Journal Article
    经常使用观察性研究来估计暴露或治疗对结果的影响。为了获得对治疗效果的无偏估计,准确测量暴露是至关重要的。一种常见的暴露错误分类是召回偏差,这发生在回顾性队列研究中,当研究对象可能不准确地回忆他们过去的暴露。特别具有挑战性的是,在自我报告的二元曝光的背景下,差异召回偏差,其中偏差可能是方向性的,而不是随机的,其程度根据所经历的结果而变化。本文做出了一些贡献:(1)即使没有验证研究,它也为平均治疗效果建立了界限;(2)它提出了基于不同假设的各种策略的多种估计方法;(3)它提出了一种敏感性分析技术来评估因果结论的稳健性,结合了先前研究的见解。通过探索各种模型错误指定场景的仿真研究,证明了这些方法的有效性。然后将这些方法用于研究儿童期身体虐待对成年后心理健康的影响。
    Observational studies are frequently used to estimate the effect of an exposure or treatment on an outcome. To obtain an unbiased estimate of the treatment effect, it is crucial to measure the exposure accurately. A common type of exposure misclassification is recall bias, which occurs in retrospective cohort studies when study subjects may inaccurately recall their past exposure. Particularly challenging is differential recall bias in the context of self-reported binary exposures, where the bias may be directional rather than random and its extent varies according to the outcomes experienced. This paper makes several contributions: (1) it establishes bounds for the average treatment effect even when a validation study is not available; (2) it proposes multiple estimation methods across various strategies predicated on different assumptions; and (3) it suggests a sensitivity analysis technique to assess the robustness of the causal conclusion, incorporating insights from prior research. The effectiveness of these methods is demonstrated through simulation studies that explore various model misspecification scenarios. These approaches are then applied to investigate the effect of childhood physical abuse on mental health in adulthood.
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  • 文章类型: Journal Article
    目的:尽管肺静脉隔离(PVI),但持续性房颤(AF)患者的复发率为50%,对于第二次治疗没有共识。我们i-STRATIFICATION研究的目的是为PVI后房颤复发患者的最佳药物和消融治疗分层提供证据。通过计算机内试验。
    方法:800名虚拟患者的队列,随着心房解剖结构的变化,电生理学,和组织结构(低电压区域,LVA),针对从离子电流到心电图的临床数据进行了开发和验证。PVI后出现AF的虚拟患者接受了12次二次治疗。
    结果:522名虚拟患者在PVI后出现持续房颤。仅包括左心房消融术的第二次消融术显示55%的疗效,仅在小右心房(<60mL)成功。当考虑额外的腔静脉-三尖瓣峡部消融时,Marshall-Plan对小左心房(<90mL)足够(66%疗效)。对于更大的左心房,需要更积极的消融方法,例如二尖瓣前线(75%的疗效)或后壁隔离加二尖瓣峡部消融(77%的疗效)。具有LVA的虚拟患者极大地受益于左心房和右心房的LVA消融(100%疗效)。相反,在没有LVA的情况下,协同消融和药物治疗可终止房颤。在没有消融的情况下,患者的离子电流底物调节了抗心律失常药物的反应,是对胺碘酮或vernakalant的最佳分层至关重要的内向流。
    结论:计算机模拟试验根据虚拟患者特征确定房颤治疗的最佳策略,证明人体建模和仿真作为临床辅助工具的力量。
    OBJECTIVE: Patients with persistent atrial fibrillation (AF) experience 50% recurrence despite pulmonary vein isolation (PVI), and no consensus is established for secondary treatments. The aim of our i-STRATIFICATION study is to provide evidence for stratifying patients with AF recurrence after PVI to optimal pharmacological and ablation therapies, through in silico trials.
    RESULTS: A cohort of 800 virtual patients, with variability in atrial anatomy, electrophysiology, and tissue structure (low-voltage areas, LVAs), was developed and validated against clinical data from ionic currents to electrocardiogram. Virtual patients presenting AF post-PVI underwent 12 secondary treatments. Sustained AF developed in 522 virtual patients after PVI. Second ablation procedures involving left atrial ablation alone showed 55% efficacy, only succeeding in the small right atria (<60 mL). When additional cavo-tricuspid isthmus ablation was considered, Marshall-PLAN sufficed (66% efficacy) for the small left atria (<90 mL). For the bigger left atria, a more aggressive ablation approach was required, such as anterior mitral line (75% efficacy) or posterior wall isolation plus mitral isthmus ablation (77% efficacy). Virtual patients with LVAs greatly benefited from LVA ablation in the left and right atria (100% efficacy). Conversely, in the absence of LVAs, synergistic ablation and pharmacotherapy could terminate AF. In the absence of ablation, the patient\'s ionic current substrate modulated the response to antiarrhythmic drugs, being the inward currents critical for optimal stratification to amiodarone or vernakalant.
    CONCLUSIONS: In silico trials identify optimal strategies for AF treatment based on virtual patient characteristics, evidencing the power of human modelling and simulation as a clinical assisting tool.
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