multivariate analysis

多变量分析
  • 文章类型: Journal Article
    最近,关于标准压疮(PU)风险评估工具的有效性,越来越多的不确定性出现了,怀疑不比临床判断好,尤其是在体弱多病的老年人群中。本研究旨在确定住院老年人PU发展和严重程度的主要临床预测变量,利用多维脆弱评估,并将它们与Braden量表进行比较。
    人群由316名患者组成,21/02/22-01/07/22期间,在(意大利)Sarzana的SanBartolomeo医院接受老年科和过渡护理。收集的信息包括记忆和实验室数据。进行了全面的老年评估,还包括人体测量和物理性能测量。采用多因素logistic分析,在二元分类测试和随后的严重程度顺序分类测试中。通过ROC曲线估计和与Braden量表的AUC比较来评估模型的最终性能。
    在人口中,152名受试者(48%)在不同严重程度发展PU。结果表明,年龄,Braden量表(流动性和摩擦/剪切子量表),Barthel秤,迷你营养评估,血红蛋白,和白蛋白是与PU发展相关的预测因子(AUC85%)。结果是优于单独使用Braden量表(AUC75%)。关于PU严重程度的预测因素的识别,4AT也成为潜在相关的。
    评估受试者的营养状况,物理性能,和功能自主性使Braden量表能够有效整合,以识别最易患PU的患者。我们的发现支持将一套全面的方法论上稳健的脆弱决定因素整合到传统的风险评估工具中。这种整合反映了患者虚弱之间的相互作用,皮肤脆弱,和PU的发展在非常老的住院患者。
    UNASSIGNED: In recent times, growing uncertainty has emerged regarding the effectiveness of standard pressure ulcer (PU) risk assessment tools, which are suspected to be no better than clinical judgment, especially in the frail and comorbid elderly population. This study aimed to identify the primary clinical predictive variables for PU development and severity in hospitalized older adults, utilizing a multidimensional frailty assessment, and compare them with the Braden scale.
    UNASSIGNED: The population consisted of 316 patients, admitted to the Geriatric Unit and Transitional Care of San Bartolomeo Hospital in Sarzana (Italy) during the period 21/02/22-01/07/22. The collected information included both anamnestic and laboratory data. A comprehensive geriatric assessment was performed, including also anthropometric and physical performance measurements. Multivariate logistic analysis was used, both in a binary classification test and in the subsequent ordinal classification test of severity levels. The final performance of the model was assessed by ROC curve estimation and AUC comparison with the Braden scale.
    UNASSIGNED: Within the population, 152 subjects (48%) developed PU at different levels of severity. The results showed that age, Braden scale (subscales of mobility and friction/shear), Barthel scale, Mini Nutritional Assessment, hemoglobin, and albumin are predictors associated with the development of PU (AUC 85%). The result is an improvement over the use of the Braden scale alone (AUC 75%). Regarding the identification of predictive factors for PU severity, 4AT also emerges as potentially relevant.
    UNASSIGNED: Assessing the subject\'s nutritional status, physical performance, and functional autonomies enables the effective integration of the Braden scale in identifying patients most susceptible to developing PU. Our findings support the integration of a comprehensive set of methodologically robust frailty determinants into traditional risk assessment tools. This integration reflects the mutual interplay between patients\' frailty, skin frailty, and PU development in very old hospitalized patients.
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  • 文章类型: Journal Article
    幼儿时期标志着执行功能成熟的关键时期,有意识地调节行为和思想的认知能力。基于正念的干预措施已显示出增强儿童执行功能的希望。本研究采用功能近红外光谱技术探讨正念训练对幼儿的影响。收集了68名儿童(41名男孩,年龄为61.8±10.7个月),随机分配到干预组(N=37,年龄为60.03±11.14个月)或对照组(N=31,年龄为59.99±10.89个月)。使用多变量和多尺度样本熵分析。结果表明:(1)干预组在所有三个执行功能任务中接受基于正念的干预后,大脑复杂性降低(ps<0.05),提示干预后神经加工机制更有效;(2)干预组和对照组的差异比较显示,在认知移位(左背外侧前额叶皮层和内侧前额叶皮层)和工作记忆任务(左背外侧前额叶皮层)期间,相关脑区存在显著差异,这证实了干预组行为结果的改善(Z=-3.674,认知转移P<0.001;Z=2.594,工作记忆P<0.01)。这些发现提高了我们对幼儿早期大脑发育的理解,并强调了基于正念的干预影响执行功能的神经机制。对早期干预促进幼儿大脑发育的意义也有所阐述。
    Early childhood marks a pivotal period in the maturation of executive function, the cognitive ability to consciously regulate actions and thoughts. Mindfulness-based interventions have shown promise in bolstering executive function in children. This study used the functional near-infrared spectroscopy technique to explore the impact of mindfulness-based training on young children. Brain imaging data were collected from 68 children (41 boys, aged 61.8 ± 10.7 months) who were randomly assigned to either an intervention group (N = 37, aged 60.03 ± 11.14 months) or a control group (N = 31, aged 59.99 ± 10.89 months). Multivariate and multiscale sample entropy analyses were used. The results showed that: (1) brain complexity was reduced in the intervention group after receiving the mindfulness-based intervention in all three executive function tasks (ps < 0.05), indicating a more efficient neural processing mechanism after the intervention; (2) difference comparisons between the intervention and control groups showed significant differences in relevant brain regions during cognitive shifting (left dorsolateral prefrontal cortex and medial prefrontal cortex) and working memory tasks (left dorsolateral prefrontal cortex), which corroborates with improved behavioral results in the intervention group (Z = -3.674, P < 0.001 for cognitive shifting; Z = 2.594, P < 0.01 for working memory). These findings improve our understanding of early brain development in young children and highlight the neural mechanisms by which mindfulness-based interventions affect executive function. Implications for early intervention to promote young children\'s brain development are also addressed.
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  • 文章类型: Journal Article
    有效的废水管理在经历水资源短缺和环境压力的地区至关重要。比如污染和气候变化。优化处理工艺对于实现环境可持续性至关重要。这项研究旨在强调有效的废水管理策略的重要性,特别是在水资源短缺的地区。我们的目标是确定影响治疗过程的关键因素。因此,我们使用多元统计方法评估物理化学参数之间的关联,包括主成分分析(PCA)和分层上升分类(HAC)。我们的发现根据有机污染水平将每月水样分为三组:第一组(7月,August,和9月)的特点是氧合水平高,有机污染明显低,指示最佳系统运行。第二组(4月,十月,十一月,和12月)表现出低氧合和低有机污染,促进污泥沉降和减少污染物。第三组(1月,二月,March,May,和6月)显示出显著的高有机污染和低氧合,这对应于不利的环境条件。我们的研究证明了多元统计方法在优化废水处理过程中的有效性,为环境可持续性和水资源管理提供重要见解。
    Effective wastewater management is crucial in regions experiencing water scarcity and environmental stressors, such as pollution and climate change. Optimizing treatment processes is essential for achieving environmental sustainability. This study aims to highlight the importance of effective wastewater management strategies, particularly in regions facing water scarcity. Our objective was to identify key factors influencing the treatment process. Therefore, we evaluated associations between physicochemical parameters using multivariate statistical methods, including Principal Component Analysis (PCA) and Hierarchical Ascendant Classification (HAC). Our findings categorize the monthly water samples into three distinct groups based on levels of organic pollution: the first group (July, August, and September) is characterized by high oxygenation levels and significantly low organic pollution, indicating optimal system operation. The second group (April, October, November, and December) exhibits low oxygenation and low organic pollution, promoting sludge settling and pollutant reduction. The third group (January, February, March, May, and June) shows significantly high organic pollution and low oxygenation, which corresponds to unfavorable environmental conditions. Our study demonstrates the effectiveness of multivariate statistical methods in optimizing wastewater treatment processes, providing crucial insights for environmental sustainability and water resource management.
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  • 文章类型: Journal Article
    Mundeswari河,印度东部一条生态受损的河流,水质恶化主要是由于其附近的人为活动。这项研究旨在全面评估河流的污染现状,并评估河水灌溉的适宜性,鉴于其广泛用于农业目的。在为期两年(2020-2022年)的四个不同采样点(SP1-SP4)进行了每月水质监测,考虑十七个水质参数。本研究采用主成分分析/因子分析(PCA/FA)和绝对主成分得分-多元线性回归(APCS-MLR)受体模型。这些方法用于辨别和量化影响Mundeswari河水质的潜在污染源。研究表明,在季风前季节,Mundeswari河的水质退化最严重。在四个采样点中,SP3表现出最高的污染水平,平均生化需氧量(BOD)和化学需氧量(COD)分别为5.36mg/L和44.72mg/L。分别。根据单向方差分析(ANOVA),大多数水质参数存在较大的空间和季节差异(P<0.05)。PCA/FA提取了四种潜在污染源,占总方差的81.5%。影响河水水质的主要因素是自然风化过程,生活污水和废物的排放,和农业径流。APCS-MLR受体模型进一步揭示了农业排水因素以及生活污水和废物的排放对Mundeswari河的影响更大。调查得出的结论是,所有灌溉适宜性指标的平均值均低于定义的阈值限值,表明所研究河流的水似乎适合灌溉。这项研究的结果可能会为制定Mundeswari河生态复兴的可持续战略做出重大贡献。
    The Mundeswari River, an ecologically distressed river in eastern India, has been subjected to water quality deterioration largely due to anthropogenic activities in its vicinity. This study aimed to comprehensively evaluate the current state of pollution in the river and assess the appropriateness of river water for irrigation, given its extensive use for agricultural purposes. Monthly water quality monitoring was undertaken at four distinct sampling sites (SP1-SP4) over a two-year period (2020-2022), considering seventeen water quality parameters. This research employed principal component analysis/factor analysis (PCA/FA) and absolute principal component score-multiple linear regression (APCS-MLR) receptor modelling. These methodologies were used to discern and quantify potential sources of pollution influencing the water quality of the Mundeswari River. The study revealed that the water quality of the Mundeswari River was most degraded during the pre-monsoon season. Among the four sampling sites, SP3 exhibited the highest level of pollution with mean biochemical oxygen demand (BOD) and chemical oxygen demand (COD) values of 5.36 mg/L and 44.72 mg/L, respectively. According to the one-way analysis of variance (ANOVA), there was considerable spatial and seasonal disparities (P < 0.05) in most water quality parameters. The PCA/FA extracted four latent pollution sources, accounting for 81.5% of the total variance. The primary factors influencing the quality of river water are natural weathering processes, discharge of domestic effluent and waste, and agricultural runoff. The APCS-MLR receptor model further revealed that agricultural drainage factors and the discharge of domestic effluent and waste had a greater impact on the Mundeswari River. The investigation concluded that the mean values of all indicators for irrigation suitability were below the defined threshold limits, indicating that the water of the studied river appears suitable for irrigation. The outcomes of this study may significantly contribute to the formulation of sustainable strategies for the ecological rejuvenation of the Mundeswari River.
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  • 文章类型: Journal Article
    背景:Alactic碱过量(ABE)是一种新的生物标志物,用于评估肾脏处理酸碱紊乱的能力,已发现这与脓毒症和休克患者的不良预后有关。本研究旨在评估急性心肌梗死(AMI)患者ABE与院内死亡风险之间的关系。
    方法:本回顾性队列研究从重症监护医学信息集市(MIMIC)-IV数据库收集AMI患者的临床数据。结果是重症监护病房(ICU)入院后的住院死亡率。单变量和多变量Cox比例风险模型用于评估ABE与AMI患者住院死亡率的相关性。风险比(HR)和95%置信区间(CI)。为了进一步探索该协会,根据年龄进行亚组分析,AKI,eGFR,脓毒症,和AMI亚型。
    结果:在总共2779例AMI患者中,502人在医院死亡。阴性ABE(HR=1.26,95CI:1.02-1.56)(中性ABE作为参考)与AMI患者住院死亡风险较高相关。但ABE不阳性(P=0.378)。亚组分析显示,在年龄>65岁的AMI患者中,ABE阴性与院内死亡风险较高显著相关(HR=1.46,95CI:1.13-1.89),eGFR<60(HR=1.35,95CI:1.05-1.74),AKI(HR=1.32,95CI:1.06-1.64),ST段抬高型急性心肌梗死(STEMI)亚型(HR=1.79,95CI:1.18-2.72),无脓毒症(HR=1.29,95CI:1.01-1.64)。
    结论:ABE阴性与AMI患者的住院死亡率显著相关。
    BACKGROUND: Alactic base excess (ABE) is a novel biomarker to evaluate the renal capability of handling acid-base disturbances, which has been found to be associated with adverse prognosis of sepsis and shock patients. This study aimed to evaluate the association between ABE and the risk of in-hospital mortality in patients with acute myocardial infarction (AMI).
    METHODS: This retrospective cohort study collected AMI patients\' clinical data from the Medical Information Mart for Intensive Care (MIMIC)-IV database. The outcome was in-hospital mortality after intensive care unit (ICU) admission. Univariate and multivariate Cox proportional hazards models were performed to assess the association of ABE with in-hospital mortality in AMI patients, with hazard ratios (HRs) and 95% confidence intervals (CI). To further explore the association, subgroup analyses were performed based on age, AKI, eGFR, sepsis, and AMI subtypes.
    RESULTS: Of the total 2779 AMI patients, 502 died in hospital. Negative ABE (HR = 1.26, 95%CI: 1.02-1.56) (neutral ABE as reference) was associated with a higher risk of in-hospital mortality in AMI patients, but not in positive ABE (P = 0.378). Subgroup analyses showed that negative ABE was significantly associated with a higher risk of in-hospital mortality in AMI patients aged>65 years (HR = 1.46, 95%CI: 1.13-1.89), with eGFR<60 (HR = 1.35, 95%CI: 1.05-1.74), with AKI (HR = 1.32, 95%CI: 1.06-1.64), with ST-segment elevation acute myocardial infarction (STEMI) subtype (HR = 1.79, 95%CI: 1.18-2.72), and without sepsis (HR = 1.29, 95%CI: 1.01-1.64).
    CONCLUSIONS: Negative ABE was significantly associated with in-hospital mortality in patients with AMI.
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  • 文章类型: Journal Article
    背景:重症监护病房(ICU)的患者极易营养不良,虽然通过鼻胃管进行肠内营养是首选方法,有无意的反流和误吸的风险。因此,临床医生已将鼻肠管(NET)作为肠内营养的替代选择。但是NET的精确定位提出了一个持续的挑战。我们提出了一种创新的方法,为参与NET放置的临床医生提供有价值的参考。
    方法:数据来自2017年10月1日至2023年10月1日期间在浙江省人民医院ICU接受NET治疗的误吸或胃喂养不耐受风险高的成年患者的病历。使用SPSS和R软件对收集的数据进行统计分析。
    结果:494例患者符合纳入和排除标准。首过成功率为81.4%(n=402)。发现患者初始NET放置的成功与角度SPC和距离CP有关,通过单变量分析确定(25.6±16.7°与41.9±18.0°,P<0.001;40.0±26.2mmvs.62.0±31.8mm,分别为P<0.001)。通过进行多元回归分析,我们发现幽门类型与NET置入成功率之间存在显著关联(OR29.559,95CI14.084-62.038,P<0.001).
    结论:角度SPC,距离CP,和幽门的类型与NET的成功初始放置独立相关。此外,幽门外侧型(OP型)患者的初始安置成功率较高.
    BACKGROUND: Patients in the intensive care unit (ICU) are highly susceptible to malnutrition, and while enteral nutrition via nasogastric tube is the preferred method, there is a risk of inadvertent reflux and aspiration. Therefore, clinicians have turned to nasointestinal tubes (NET) for enteral nutrition as an alternative option. But the precise localization of NET presents an ongoing challenge. We proposed an innovative approach to provide a valuable reference for clinicians involved in NET placement.
    METHODS: Data were obtained retrospectively from the medical records of adult patients with a high risk of aspiration or gastric feeding intolerance who had a NET placed in the ICU of Zhejiang Provincial People\'s Hospital between October 1, 2017, and October 1, 2023. The collected data were subjected to statistical analysis using SPSS and R software.
    RESULTS: There were 494 patients who met the inclusion and exclusion criteria. The first-pass success rate was 81.4% (n = 402). The success of a patient\'s initial NET placement was found to be associated with Angle SPC and Distance CP, as determined by univariate analysis (25.6 ± 16.7° vs. 41.9 ± 18.0°, P < 0.001; 40.0 ± 26.2 mm vs. 62.0 ± 31.8 mm, P < 0.001, respectively). By conducting a multivariate regression analysis, we identified a significant association between pyloric types and the success rate of placing NET (OR 29.559, 95%CI 14.084-62.038, P < 0.001).
    CONCLUSIONS: Angle SPC, Distance CP, and the type of pylorus are independently associated with successful initial placement of NET. Besides, patients with the outside type of pylorus (OP-type) exhibit a higher rate of initial placement success.
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  • 文章类型: Journal Article
    目的:观察性研究发现神经质与脑小血管病(CSVD)相关。我们旨在探讨神经质的不同成分与CSVD之间的因果关系。
    方法:进行了双样本孟德尔随机化(MR)研究,以探索神经质的三个遗传上不同的亚簇之间的双向因果关系(抑郁情绪,担心,以及对环境压力和逆境的敏感性[SESA])和使用公开可用的全基因组关联研究(GWAS)数据的CSVD的MRI标记。主要因果估计采用逆方差加权(IVW)法。进行了替代MR方法和广泛的敏感性分析,以确保研究结果的稳健性。多变量MR(MVMR)分析用于评估直接因果效应,并调整其他已知的CSVD危险因素。
    结果:遗传确定的SESA与降低的各向异性分数(FA)显着相关(β:-1.94,95CI:-3.04至-0.84,p=5.29e-4),与标称显著水平的平均扩散率(MD)(β=1.55,95CI:0.29至2.81,p=0.016)和白质高强度(WMH)(β=0.25,95%CI:0.03至0.47,p=0.029)增加相关。MVMR分析表明,在考虑体重指数(BMI)后,显着关联仍然显着。吸烟,饮酒,2型糖尿病(T2D),高血压,和抑郁症。另外两个神经质亚簇(抑郁情绪和忧虑)对MRI标记没有显著的因果效应。在使用MRI标记作为暴露的反向MR分析中,未发现显著关联.
    结论:本研究支持SESA在CSVD发展中的随意性作用。需要进一步的研究来探索潜在的机制。
    OBJECTIVE: Neuroticism was found to be associated with cerebral small vessel disease (CSVD) in observational studies. We aimed to explore the causal relationship between distinct components of neuroticism and CSVD.
    METHODS: Two-sample mendelian randomization (MR) study was conducted to explore the bidirectional causal relationships between three genetically distinct subclusters of neuroticism (depressed affect, worry, and sensitivity to environmental stress and adversity [SESA]) and MRI markers of CSVD using publicly available genome-wide association studies (GWAS) data. Inverse variance weighted (IVW) method was used for the primary causal estimates. Alternative MR approaches and extensive sensitivity analyses were conducted to ensure the robustness of the findings. Multivariable MR (MVMR) analysis was used to estimate the direct causal effects with adjustment of other known risk factors for CSVD.
    RESULTS: Genetically determined SESA was significantly associated with reduced fractional anisotropy (FA) (beta: -1.94, 95%CI: -3.04 to -0.84, p=5.29e-4), and associated with increased mean diffusivity (MD) (beta=1.55, 95%CI: 0.29 to 2.81, p=0.016) and white matter hyperintensities (WMH) (beta=0.25, 95% CI: 0.03 to 0.47, p=0.029) at the nominally significant level. MVMR analysis suggested the significant associations remained significant after accounting for body mass index (BMI), smoking, alcohol drinking, type 2 diabetes (T2D), hypertension, and depression. The other two neuroticism subclusters (depressed affect and worry) didn\'t have significant causal effects on the MRI markers. In the reverse MR analysis with the MRI markers as exposures, no significant associations were found.
    CONCLUSIONS: This study supported the casual role of SESA in the development of CSVD. Further research to explore the underlying mechanism are warranted.
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  • 文章类型: Journal Article
    背景:我们研究的目的是调查结核病患者的血清壳三糖苷酶水平,它与微生物学和临床参数的关系,以及对治疗的反应。
    方法:这项纵向小组研究包括149例确诊的结核病患者。在处理开始和结束时测量血清壳三糖苷酶活性。使用单变量和多变量逻辑回归分析探索与壳三糖苷酶活性相关的因素。
    结果:在149名研究参与者中,71(47.7%)为女性。平均年龄为53.0(SD=18.2)。大多数病例是新的118例(79.2例),主要有145人(97.3%)患有肺结核。一半以上的患者痰涂片阳性91例(61.1%),而培养阳性146例(98%)。根据放射学发现,92例(63.4%)患者发现空洞性病变。抗结核治疗与血清壳三糖苷酶水平显著降低相关(<0.001)。新的结核病治疗(OR=4.41%;95%CI=1.20-9.89),发现空洞性病变(OR=3.86;95CI=0,59-26.57)与壳三糖苷酶活性降低显着相关。
    结论:我们的研究结果表明,血清壳三糖苷酶值是开始抗结核治疗和治疗监测的重要生物标志物,因为血清壳三糖苷酶水平的降低可以预测结核病患者的良好治疗反应。需要进一步的研究来探索这些,和其他与结核病患者的壳三糖苷酶活性相关的因素。
    BACKGROUND: The aim of our study was to investigate serum chitotriosidase level in tuberculosis patients, its relationship with microbiological and clinical parameters, and response to treatment.
    METHODS: This longitudinal panel study included 149 patients with confirmed TB disease. Serum chitotriosidase activity was measured at the beginning and the end of treatment. Factors associated with chitotriosidase activity were explored using univariate and multivariable logistic regression analysis.
    RESULTS: Out of 149 study participants, 71(47.7%) were female. The mean age was 53.0 (SD = 18.2). Majority of cases were new 118(79.2), predominantly 145 (97.3%) having pulmonary tuberculosis. More than half of the patients were sputum smear positive 91 (61.1%) while culture positive in 146 (98%) of them. According to radiological findings, cavitary lesions were found in 92 (63.4%) patients. Anti TB treatment was associated with significant decrease in serum chitotriosidase level (< 0.001). New TB treatment (OR = 4.41%;95% CI = 1.20-9.89), and cavitary lesions (OR = 3.86;95%CI = 0,59-26.57) were found to be significantly associated with decrease of chitotriosidase activity.
    CONCLUSIONS: The results of our study showed that serum chitotriosidase values are strong biomarkers for starting anti TB treatment and for treatment monitoring, since decrease in serum chitotriosidase level can predict favorable treatment response in patients with tuberculosis. Further studies are needed to explore these, and other factors associated with chitotriosidase activity among tuberculosis patients.
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  • 文章类型: Journal Article
    在回归分析中对结果与多个自变量之间的关联进行建模时,研究人员通常会执行数据驱动的变量选择。变量选择可以提高可解释性,模型的简约和/或预测准确性。然而,变量选择也会产生负面影响,例如错误排除重要变量或包含噪声变量,回归系数的有偏估计,低估了标准误差和无效置信区间,以及模型的不稳定性。虽然变量选择的潜在优点和缺点已经在文献中讨论了几十年,很少有大规模的模拟研究对数据驱动的变量选择方法对结果模型的影响进行了中立的比较。我们提出了一个模拟研究的协议,该协议将评估不同的变量选择方法:前向选择,逐步向前选择,落后淘汰,增强后向消除,单变量选择,单变量选择,然后是向后消除,和惩罚似然法(Lasso,放松的套索,自适应套索)。这些方法将在错误包含和/或排除变量方面进行比较,对估计回归系数的偏差和方差的影响,系数的置信区间的有效性,估计变量重要性排序的准确性,以及所选模型的预测性能。我们在低维设置(20个独立变量,10个真实预测变量和10个噪声变量)中同时考虑线性和逻辑回归。模拟将基于国家健康和营养检查调查(NHANES)的实际数据。在执行模拟之前发布此研究协议增加了透明度,并允许将其他专家的观点集成到研究设计中。
    Researchers often perform data-driven variable selection when modeling the associations between an outcome and multiple independent variables in regression analysis. Variable selection may improve the interpretability, parsimony and/or predictive accuracy of a model. Yet variable selection can also have negative consequences, such as false exclusion of important variables or inclusion of noise variables, biased estimation of regression coefficients, underestimated standard errors and invalid confidence intervals, as well as model instability. While the potential advantages and disadvantages of variable selection have been discussed in the literature for decades, few large-scale simulation studies have neutrally compared data-driven variable selection methods with respect to their consequences for the resulting models. We present the protocol for a simulation study that will evaluate different variable selection methods: forward selection, stepwise forward selection, backward elimination, augmented backward elimination, univariable selection, univariable selection followed by backward elimination, and penalized likelihood approaches (Lasso, relaxed Lasso, adaptive Lasso). These methods will be compared with respect to false inclusion and/or exclusion of variables, consequences on bias and variance of the estimated regression coefficients, the validity of the confidence intervals for the coefficients, the accuracy of the estimated variable importance ranking, and the predictive performance of the selected models. We consider both linear and logistic regression in a low-dimensional setting (20 independent variables with 10 true predictors and 10 noise variables). The simulation will be based on real-world data from the National Health and Nutrition Examination Survey (NHANES). Publishing this study protocol ahead of performing the simulation increases transparency and allows integrating the perspective of other experts into the study design.
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  • 文章类型: Journal Article
    目的:精神分裂症的特征是静息状态自发的大脑活动改变;然而,目前尚不清楚不同空间尺度的变异是否能够有效区分患者和健康对照.此外,这些改变的遗传基础仍然缺乏阐明。我们旨在在这项研究中解决这些问题,以更好地了解精神分裂症的大脑改变及其潜在的遗传因素。
    方法:一个由103名诊断为精神分裂症的个体和110名健康对照者组成的队列接受了静息态功能MRI扫描。使用区域同质性(ReHo)度量在四个空间尺度上评估自发性大脑活动:体素水平(1级)和区域水平(2-4:272,53,17个区域,分别)。对于每个空间尺度,多变量模式分析将精神分裂症患者与健康对照进行分类,并进行了转录组-神经影像学关联分析,以建立精神分裂症中基因表达数据与ReHo改变之间的联系。
    结果:所有空间尺度的ReHo指标有效地将精神分裂症与健康对照区分开来。量表2显示出最高的分类准确率,为84.6%,其次是1级(83.1%)和3级(78.5%),而量表4的准确度最低(74.2%)。此外,转录组-神经影像学关联分析显示,在4个空间尺度上,不仅存在共有的生物过程,而且存在独特的富集生物过程.这些相关的生物过程主要与免疫反应有关,炎症,突触信号,离子通道,细胞发育,髓鞘形成,和运输活动。
    结论:这项研究强调了多尺度ReHo作为精神分裂症诊断中一种有价值的神经影像学生物标志物的潜力。通过阐明这种疾病的ReHo改变的复杂分子基础,这项研究不仅增强了我们对其病理生理学的理解,但也为精神分裂症的基因诊断和治疗的未来发展铺平道路。
    OBJECTIVE: Schizophrenia is characterized by alterations in resting-state spontaneous brain activity; however, it remains uncertain whether variations at diverse spatial scales are capable of effectively distinguishing patients from healthy controls. Additionally, the genetic underpinnings of these alterations remain poorly elucidated. We aimed to address these questions in this study to gain better understanding of brain alterations and their underlying genetic factors in schizophrenia.
    METHODS: A cohort of 103 individuals with diagnosed schizophrenia and 110 healthy controls underwent resting-state functional MRI scans. Spontaneous brain activity was assessed using the regional homogeneity (ReHo) metric at four spatial scales: voxel-level (Scale 1) and regional-level (Scales 2-4: 272, 53, 17 regions, respectively). For each spatial scale, multivariate pattern analysis was performed to classify schizophrenia patients from healthy controls, and a transcriptome-neuroimaging association analysis was performed to establish connections between gene expression data and ReHo alterations in schizophrenia.
    RESULTS: The ReHo metrics at all spatial scales effectively discriminated schizophrenia from healthy controls. Scale 2 showed the highest classification accuracy at 84.6%, followed by Scale 1 (83.1%) and Scale 3 (78.5%), while Scale 4 exhibited the lowest accuracy (74.2%). Furthermore, the transcriptome-neuroimaging association analysis showed that there were not only shared but also unique enriched biological processes across the four spatial scales. These related biological processes were mainly linked to immune responses, inflammation, synaptic signaling, ion channels, cellular development, myelination, and transporter activity.
    CONCLUSIONS: This study highlights the potential of multi-scale ReHo as a valuable neuroimaging biomarker in the diagnosis of schizophrenia. By elucidating the complex molecular basis underlying the ReHo alterations of this disorder, this study not only enhances our understanding of its pathophysiology, but also pave the way for future advancements in genetic diagnosis and treatment of schizophrenia.
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