structural equation modeling

结构方程建模
  • 文章类型: Journal Article
    结构方程建模(SEM)中模型拟合的流行度量是标准化均方根残差(SRMR)拟合指数。等效测试已用于评估结构方程模型(SEM)中的模型拟合,但尚未应用于SRMR。因此,本研究提出了基于等效测试的SRMR(ESRMR)拟合测试。介绍了ESRMR的几种变体,结合不同的等价界限和置信区间的计算方法。蒙特卡罗模拟研究将这些新颖的测试与评估模型拟合的传统方法进行了比较。结果表明,基于置信区间的分析计算的某些ESRMR测试正确地拒绝了拟合不良的模型,并且可以很好地检测拟合良好的模型。我们还提供了一个具有真实数据的说明性示例,以演示如何将ESRMR纳入模型拟合评估和报告中。我们的建议是,除了在SEM中进行模型拟合报告的描述性拟合指数外,还应提供ESRMR测试。
    A popular measure of model fit in structural equation modeling (SEM) is the standardized root mean squared residual (SRMR) fit index. Equivalence testing has been used to evaluate model fit in structural equation modeling (SEM) but has yet to be applied to SRMR. Accordingly, the present study proposed equivalence-testing based fit tests for the SRMR (ESRMR). Several variations of ESRMR were introduced, incorporating different equivalence bounds and methods of computing confidence intervals. A Monte Carlo simulation study compared these novel tests with traditional methods for evaluating model fit. The results demonstrated that certain ESRMR tests based on an analytic computation of the confidence interval correctly reject poor-fitting models and are well-powered for detecting good-fitting models. We also present an illustrative example with real data to demonstrate how ESRMR may be incorporated into model fit evaluation and reporting. Our recommendation is that ESRMR tests be presented in addition to descriptive fit indices for model fit reporting in SEM.
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  • 文章类型: Journal Article
    由于相当大的神经发育变化,青春期是重度抑郁症(MDD)发作的脆弱时期。先前在抑郁症青年中进行的扩散张量成像(DTI)研究有异质参与者,由于疾病的慢性和药物混淆,对早期病理的评估具有挑战性。这项研究利用全脑DTI和图论方法来探测与首发相关的结构网络拓扑中的白质(WM)异常和干扰,治疗初治小儿MDD。参与者包括36个第一集,患有MDD的未用药青少年(平均年龄15.8岁)和29名年龄和性别匹配的健康对照(平均年龄15.2岁)。与对照组相比,MDD组的内外囊显示出降低的分数各向异性,揭示早发性抑郁症WM中断的新区域。右丘脑和颞上回被确定为网络枢纽,在该枢纽中,介数中心性变化介导了WM异常与抑郁严重程度之间的联系。结合人口统计的诊断模型,DTI,和网络指标使用神经网络算法实现了0.88的AUROC和0.80的F1得分。通过检查第一集,初治患者,这项工作确定了新的WM异常和潜在的因果通路,该通路通过脑中心区域结构网络改变将WM损伤与症状严重程度联系起来.
    Puberty is a vulnerable period for the onset of major depressive disorder (MDD) due to considerable neurodevelopmental changes. Prior diffusion tensor imaging (DTI) studies in depressed youth have had heterogeneous participants, making assessment of early pathology challenging due to illness chronicity and medication confounds. This study leveraged whole-brain DTI and graph theory approaches to probe white matter (WM) abnormalities and disturbances in structural network topology related to first-episode, treatment-naïve pediatric MDD. Participants included 36 first-episode, unmedicated adolescents with MDD (mean age 15.8 years) and 29 age- and sex-matched healthy controls (mean age 15.2 years). Compared to controls, the MDD group showed reduced fractional anisotropy in the internal and external capsules, unveiling novel regions of WM disruption in early-onset depression. The right thalamus and superior temporal gyrus were identified as network hubs where betweenness centrality changes mediated links between WM anomalies and depression severity. A diagnostic model incorporating demographics, DTI, and network metrics achieved an AUROC of 0.88 and a F1 score of 0.80 using a neural network algorithm. By examining first-episode, treatment-naïve patients, this work identified novel WM abnormalities and a potential causal pathway linking WM damage to symptom severity via regional structural network alterations in brain hubs.
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  • 文章类型: Journal Article
    目的:本研究旨在评估预测因子之间的不同途径,如接合性,非典型吞咽,嘴巴呼吸,母乳喂养和奶瓶喂养相关的前开放咬伤(AOB)的双胞胎。
    方法:这项研究是在3-15岁的单卵(MZ)和双卵(DZ)双胞胎儿童中进行的。AOB,非典型吞咽,嘴巴呼吸,喂养类型,瓶子使用的持续时间,在口腔检查期间记录睡眠期间的张口状态。进行了偏最小二乘结构方程模型(PLS-SEM)和sobel检验,以评估变量之间对AOB的总体和间接影响。
    结果:共有404名儿童(29.2%MZ;70.8%DZ)参加了这项研究。PLS-SEM模型中的接合度对口腔呼吸的影响具有统计学意义。相反,确定口呼吸影响非典型吞咽(p=0.001)。非典型吞咽触发AOB(p=0.001)。非典型吞咽在AOB和口腔呼吸之间具有中介作用(p=0.020)。口呼吸引起非典型吞咽,因此间接增加AOB的可能性。母乳喂养可降低AOB发生率(p=0.023),奶瓶喂养增加AOB发生率(p=0.046)。sobel测试表明,口腔呼吸的完全中介变量特征在接合性与非典型吞咽之间的负相关方面具有统计学意义。
    结论:PLS-SEM模型显示,口腔呼吸触发非典型吞咽,非典型吞咽触发AOB。由于这一连串的关系,观察到接合性对AOB的间接影响。根据Sobel测试,合子对通过口呼吸的非典型吞咽有间接影响,而口腔呼吸通过非典型吞咽对AOB有积极的间接影响。
    结论:本研究确定了不同因素与AOB存在之间的关系。这项研究的结果详细证明了AOB与接合性之间的关系,非典型吞咽,嘴巴呼吸,母乳喂养和奶瓶喂养。不进食对AOB的频率有降低的作用。在营养形式中,母乳喂养通过使口面部肌肉工作来确保口颌系统的正常发育。
    OBJECTIVE: This study aimed to assess the different pathways between predictor factors such as zygosity, atypical swallowing, mouth breathing, breastfeeding and bottle feeding related to anterior open bite (AOB) in twins.
    METHODS: The study was conducted in monozygotic (MZ) and dizygotic (DZ) twin children aged 3-15 years. AOB, atypical swallowing, mouth breathing, feeding type, duration of bottle use, and mouth opening status during sleep were recorded during oral examination. Partial least squares structural equation model (PLS-SEM) and sobel tests were performed to assess the total and indirect effects among the variables on AOB.
    RESULTS: A total of 404 children (29.2% MZ;70.8% DZ) participated in this study. The effect of zygosity on mouth breathing in the PLS-SEM model was statistically significant. Conversely, it was determined that mouth breathing effected that atypical swallowing (p = 0.001). Atypical swallowing triggered AOB (p = 0.001). The atypical swallowing has a mediation effect between AOB and mouth breathing (p = 0.020). Mouth breathing causes atypical swallowing and therefore indirectly increases the likelihood of AOB. While breastfeeding decreases AOB incidence (p = 0.023), bottle feeding increases AOB incidence (p = 0.046). The sobel tests show that the fully mediator variable feature of mouth breathing is statistically significant in the negative relation between zygosity and atypical swallowing.
    CONCLUSIONS: The PLS-SEM model showed that mouth breathing triggers atypical swallowing and atypical swallowing triggers AOB. As a result of this chain of relationships, an indirect effect of zygosity on AOB was observed. According to sobel tests, zygosity has an indirect effect on atypical swallowing through mouth breathing, while mouth breathing has a positive indirect effect on AOB through atypical swallowing.
    CONCLUSIONS: This study identified the relationships between different factors and the presence of AOB. The findings of this study demonstrate in detail the relationships between AOB and zygosity, atypical swallowing, mouth breathing, breastfeeding and bottle feeding. Brestfeeding has a reducing effect on the frequency of AOB. Among the nutritional forms, breastfeeding ensures the proper development of the stomatognathic system by working the oro-facial muscles.
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  • 文章类型: Journal Article
    我们展示了R包galamm,其目标是在结构方程模型和混合效应模型之间提供共同点。它支持具有任意数量的交叉或嵌套随机效应的模型的估计,平滑样条,混合响应类型,因素结构,异方差残差,和数据随机丢失。使用稀疏矩阵方法和自动微分的实现确保了计算效率。我们在这里简要介绍实施的方法,给出该软件包的概述和演示其使用的示例。
    We present the R package galamm, whose goal is to provide common ground between structural equation modeling and mixed effect models. It supports estimation of models with an arbitrary number of crossed or nested random effects, smoothing splines, mixed response types, factor structures, heteroscedastic residuals, and data missing at random. Implementation using sparse matrix methods and automatic differentiation ensures computational efficiency. We here briefly present the implemented methodology, give an overview of the package and an example demonstrating its use.
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  • 文章类型: Journal Article
    研究人员可能拥有他们希望进行荟萃分析的研究的原始数据。这项研究的目的是确定,说明,并为可获得原始数据的研究人员比较一系列可能的分析选项,想要将结构方程模型(SEM)拟合到这些数据。这项研究说明了直接分析原始数据的技术,如多级和多组SEM,和基于汇总统计的技术,如基于相关性的元分析结构方程模型(MASEM),讨论程序上的差异,能力,和结果。这是通过使用开源软件分析先前发布的数据集集合来完成的。使用涉及SEM的不同技术,将反映计划行为理论的路径模型拟合到这些数据集。除了处理缺失数据的差异外,包括学习水平主持人的能力,和异质性的概念化,结果显示不同方法的参数估计和标准误差存在差异。需要进一步的研究来适当地制定指南,以应用研究人员寻求进行个人参与者数据MASEM。
    Researchers may have at their disposal the raw data of the studies they wish to meta-analyze. The goal of this study is to identify, illustrate, and compare a range of possible analysis options for researchers to whom raw data are available, wanting to fit a structural equation model (SEM) to these data. This study illustrates techniques that directly analyze the raw data, such as multilevel and multigroup SEM, and techniques based on summary statistics, such as correlation-based meta-analytical structural equation modeling (MASEM), discussing differences in procedures, capabilities, and outcomes. This is done by analyzing a previously published collection of datasets using open source software. A path model reflecting the theory of planned behavior is fitted to these datasets using different techniques involving SEM. Apart from differences in handling of missing data, the ability to include study-level moderators, and conceptualization of heterogeneity, results show differences in parameter estimates and standard errors across methods. Further research is needed to properly formulate guidelines for applied researchers looking to conduct individual participant data MASEM.
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  • 文章类型: Journal Article
    背景:小气道功能障碍不仅影响哮喘控制,而且对哮喘患者的心理和/或社会活动也有不良影响。然而,很少有长期观察性研究探讨哮喘急性发作患者小气道功能障碍与哮喘控制和健康相关生活质量之间的复杂关系.
    方法:该研究招募了223名哮喘加重患者(即在过去一年中至少有一次哮喘发作的患者)和228名哮喘未加重患者(即在过去一年中没有哮喘发作的患者)。我们使用脉冲振荡法评估了哮喘急性发作患者的SAD。在随访一年内的每个评估时间点,主治医师对患者进行病例调查。我们分析了SAD与一般特征(年龄,肥胖,吸烟史),2型炎症(血液嗜酸性粒细胞,呼出一氧化氮),哮喘急性发作患者的FEV1以及哮喘控制(ACT)和健康相关生活质量(mini-AQLQ),并构建了一个结构方程模型来评估这些临床变量的因果关系。
    结果:哮喘加重患者的SAD患病率高达75%。SAD与哮喘控制不佳和健康相关的生活质量差有关。结构方程模型表明,年龄,肥胖,FeNO,FEV1是SAD的独立预测因子。SAD是哮喘控制的主要决定因素,进而影响与健康相关的生活质量。FEV1和年龄直接影响哮喘控制,并通过哮喘控制影响健康相关的生活质量。此外,FEV1与小气道功能障碍之间以及哮喘控制与健康相关生活质量之间存在双向关系.
    结论:小气道在哮喘的早期阶段就有影响。小气道功能异常可显著增加哮喘患者的气道阻力,同时恶化他们的临床症状。此外,衰老也是哮喘控制的关键危险因素.尤其是,小气道功能障碍将哮喘控制与健康相关生活质量联系起来.
    BACKGROUND: Small airway dysfunction not only affects asthma control, but also has adverse effects on the psychological and/or social activities of asthma patients. However, few long-term observational studies have explored the complex relationship between small airway dysfunction and asthma control and health-related quality of life in patients with asthma exacerbations.
    METHODS: The study recruited 223 patients with exacerbations of asthma (i.e. those with at least one asthma attack over the past year) and 228 patients without exacerbations of asthma (i.e. those without asthma attacks over the past year). We evaluated SAD in patients with asthma exacerbations using impulse oscillometry method. At each evaluation time point within one year of follow-up, the attending physician conducts a case investigation of the patients. We analyzed the correlation between SAD and general characteristics (age, obesity, smoking history), type 2 inflammation (blood eosinophils, exhaled nitric oxide), FEV1, as well as asthma control (ACT) and health-related quality of life (mini-AQLQ) in patients with asthma exacerbations, and constructed a structural equation model to evaluate the causality of these clinical variables.
    RESULTS: The SAD prevalence in patients with asthma exacerbation is as high as 75%. SAD is connected with poor asthma control and poor health-related quality of life. The structural equation model indicates that age, obesity, FeNO, and FEV1 are independent predictive factors of SAD. SAD is the main determinant factor of asthma control, which in turn affected health-related quality of life. FEV1 and age directly affect asthma control and affect health-related quality of life through asthma control. In addition, there is a bidirectional relationship between FEV1 and small airway dysfunction and between asthma control and health-related quality of life.
    CONCLUSIONS: Small airways are involved from an early stage in asthma. Abnormal function of the small airways can significantly increase airway resistance in asthma patients, while worsening their clinical symptoms. In addition, aging is also a key risk factor for asthma control. Especially, small airway dysfunction links asthma control with health-related quality of life.
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  • 文章类型: Journal Article
    由于复杂的机制,湿地生态系统中的甲烷通量(FCH4)差异很大。具有挑战性的准确估计。环境驱动因素之间的相互作用,虽然在调节FCH4方面至关重要,但还没有得到很好的理解。这里,首先使用来自不同湿地类型和气候区的22个地点的396,322个半小时测量结果分析了六个环境驱动因素对FCH4的交互影响。结果表明,土壤温度,潜热湍流通量,和生态系统呼吸主要对FCH4产生直接影响,而气温和总初级生产力主要通过与其他驱动因素相互作用而产生间接影响。强调了FCH4调控机制的显著空间变异性,不同的司机表现出不同的直接,间接,以及网站之间的总影响。然后将这种空间变异性与特定地点的年平均气温(17.7%)和地下水位(9.0%)条件相关联,允许将CH4来源分为四组,并确定了关键驱动因素。因此,提出了一种使用具有三个关键驱动因素的随机森林模型的改进估计方法,以更少的输入需求提供准确的FCH4预测。通过明确考虑环境相互作用并解释空间变异性,这项研究增强了我们对调节CH4排放机制的理解,有助于更有效地建模和估计湿地FCH4。
    Methane fluxes (FCH4) vary significantly across wetland ecosystems due to complex mechanisms, challenging accurate estimations. The interactions among environmental drivers, while crucial in regulating FCH4, have not been well understood. Here, the interactive effects of six environmental drivers on FCH4 were first analyzed using 396,322 half-hourly measurements from 22 sites across various wetland types and climate zones. Results reveal that soil temperature, latent heat turbulent flux, and ecosystem respiration primarily exerted direct effects on FCH4, while air temperature and gross primary productivity mainly exerted indirect effects by interacting with other drivers. Significant spatial variability in FCH4 regulatory mechanisms was highlighted, with different drivers demonstrated varying direct, indirect, and total effects among sites. This spatial variability was then linked to site-specific annual-average air temperature (17.7%) and water table (9.0%) conditions, allowing the categorization of CH4 sources into four groups with identified critical drivers. An improved estimation approach using a random forest model with three critical drivers was consequently proposed, offering accurate FCH4 predictions with fewer input requirements. By explicitly accounting for environmental interactions and interpreting spatial variability, this study enhances our understanding of the mechanisms regulating CH4 emissions, contributing to more efficient modeling and estimation of wetland FCH4.
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  • 文章类型: Journal Article
    本文探讨了青春期性别与体育参与的交集,专注于传统上男性主导的运动,如足球。我们旨在基于计划行为理论(TPB)开发一个结构模型,以研究性别差异的模式和影响青少年参与足球的因素。我们使用结构方程模型(SEM)分析了1147名青少年的数据。结果表明,态度的混合,主观规范,感知行为控制,过去的行为有效地预测了青少年参与足球的意愿。此外,这项研究调查了感知行为控制的作用,过去的行为,和实际足球参与中的行为意图,在从过去的行为到意图和随后的行为的进展中发现显著的性别差异。这项研究强调了性别在足球参与中的复杂作用,并为增加女孩参与这项运动提供了战略见解。我们的研究为未来关于提高女孩参与足球的研究奠定了基础。
    This paper explores the intersection of gender and sports participation in adolescence, focusing on traditionally male-dominated sports like football. We aim to develop a structural model based on the Theory of Planned Behavior (TPB) to examine gender-differentiated patterns and factors influencing adolescent participation in football. We analyzes data from 1,147 adolescents using Structural Equation Modeling (SEM). The results indicate that a blend of attitudes, subjective norms, perceived behavioral control, and past behavior effectively predicts adolescents\' willingness to engage in football. Moreover, the study investigates the roles of perceived behavioral control, past behavior, and behavioral intentions in actual football participation, uncovering significant gender disparities in the progression from past behavior to intentions and subsequent behavior. This research highlights the complex role of gender in football participation and provides strategic insights for increasing girls\' involvement in the sport. Our study sets the stage for future research on enhancing girls\' participation in football.
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  • 文章类型: Journal Article
    社会关系模型(SRM)是分析源于循环设计的二进数据的标准方法。该模型可用于估计相关系数,该相关系数反映了样本或群体水平上个人和二元组判断的总体互惠性或准确性。在社会关系结构方程建模框架内,在随机测量和经典检验理论的统计基础上,我们展示了如何修改多指标SRM,以捕获个体间和二元间的相互参与差异或个体间的相互准确性差异。所有模型都在包含模仿措施的开放获取循环数据集上进行了说明,喜欢,和元喜欢(被喜欢的信念)。结果表明,在与某人互动后,更强烈地参与互惠模仿的人更喜欢,而高估自己的受欢迎程度与更少的人被喜欢密切相关。进一步的应用,讨论了模型的优点和局限性。
    The social relations model (SRM) is the standard approach for analyzing dyadic data stemming from round-robin designs. The model can be used to estimate correlation-coefficients that reflect the overall reciprocity or accuracy of judgements for individual and dyads on the sample- or population level. Within the social relations structural equation modeling framework and on the statistical grounding of stochastic measurement and classical test theory, we show how the multiple indicator SRM can be modified to capture inter-individual and inter-dyadic differences in reciprocal engagement or inter-individual differences in reciprocal accuracy. All models are illustrated on an open-access round-robin data set containing measures of mimicry, liking, and meta-liking (the belief to be liked). Results suggest that people who engage more strongly in reciprocal mimicry are liked more after an interaction with someone and that overestimating one\'s own popularity is strongly associated with being liked less. Further applications, advantages and limitations of the models are discussed.
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  • 文章类型: Journal Article
    背景:尽管COVID-19具有高度传染性并传播到多个国家,大学社区忽视了预防措施。五十多年来,健康信念模型(HBM)已成为健康行为中广泛使用的概念框架。结构方程模型(SEM)分析是一种先进的统计方法,能够纠正基本模型的故障并显示复杂的关系。因此,本研究旨在确定COVID-19预防行为的程度,并使用HBM和SEM分析确定其相关因素。
    方法:一项基于机构的横断面研究于2021年4月10日至5月10日在埃塞俄比亚贡达尔大学的学术人员中进行。DanielSoper的样本量计算器用于确定样本量。按比例分配给每个校园,然后采用简单的随机抽样技术来选择研究对象。一个预先测试,采用结构化问卷收集数据。采用结构方程模型分析显示了健康信念模型构建及其对预防行为的影响之间的关系。
    结果:共有602名学术人员参加。良好的COVID-19预防行为的幅度为24.8%。HBM解释了预防行为差异的55%。感知障碍(β=-0.37,p<0.05),自我效能感(β=0.32,p<0.05),感知易感性(β=0.23,p<0.05),感知获益(β=0.16,p<0.05)是COVID19预防行为的直接显著预测因素。
    结论:只有四分之一的学术人员具有良好的COVID-19预防行为。HBM解释了预防行为和感知障碍的大量差异,好处,易感性,自我效能感与预防行为显著相关。应设计和实施考虑到这些重要感知的精心策划的干预措施,以提高COVID-19预防行为。
    BACKGROUND: Despite COVID-19 being highly contagious and spreading to several countries, the university community has overlooked prevention measures. For more than five decades, the Health Belief Model (HBM) has been a widely used conceptual framework in health behavior. structural equation modeling(SEM) analysis is an advanced statistical method capable of rectifying failures of the basic models and showing complex relations Thus this study aimed to determine the magnitude of COVID-19 prevention behavior and identify its associated factors using HBM and SEM analysis.
    METHODS: An institutional-based cross-sectional study was conducted among academic staff of the University of Gondar in Ethiopia from April 10 to May 10/2021. Daniel Soper\'s sample size calculator was used to determine the sample size. Proportional allocation to each campus followed by a simple random sampling technique was employed to select study subjects. A pre-tested, structured questionnaire was used to collect the data. Structural equation modeling analysis was employed to show the relationship between health belief model constructs and their effect on preventive behavior.
    RESULTS: A total of 602 academic staff participated. The magnitude of good COVID-19 preventive behavior was 24.8%. The HBM explained 55% of the variance in preventive behavior. Perceived barriers (β = -0.37, p < 0.05), self-efficacy (β = 0.32, p < 0.05), perceived susceptibility (β = 0.23, p < 0.05), and perceived benefit (β = 0.16, p < 0.05) were the direct significant predictors of COVID 19 prevention behavior.
    CONCLUSIONS: only a quarter of the academic staff have good COVID-19 preventive behavior. The HBM explained a great amount of variance in preventive behavior and Perceived barriers, benefits, susceptibility, and self-efficacy significantly associated with prevention behavior. Carefully planned intervention that considers those significant perceptions should be designed and implemented to raise COVID-19 prevention behavior.
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