Statistical methods

统计方法
  • 文章类型: Journal Article
    背景:城乡医疗差距,包括家庭医疗保健,全球坚持。随着人口老龄化和医疗进步,对家庭保健服务的需求上升,保证对家庭保健差距进行调查。我们的研究旨在1)调查农村程度与家庭医疗质量之间的关系,和2)评估城乡家庭保健机构(HHA)之间家庭保健质量的时间差异和变化,结合地理空间分布的分析,以可视化潜在的模式。
    方法:本研究分析了医疗保险和医疗补助服务中心(CMS)网站上列出的HHA数据,涵盖2010年至2022年期间。每种HHA的数据分为城市和农村类别。我们采用面板数据分析来检验乡村对家庭医疗质量的影响,特别关注入院率和急诊室(ER)就诊率。使用Wilcoxon检验评估城市和农村HHA之间的差异,结果通过线和点图和热图可视化,以全面说明趋势和差异。
    结果:在面板数据分析中,乡村性被证明是住院率和ER就诊率的最重要变量。从2010年到2022年,与农村HHA相比,城市HHA的住院率和急诊室就诊率一直显着降低。纵向,城乡HHA住院率的差距正在缩小,虽然急诊室就诊率差距越来越大。2022年,以农村地区比例较高为特征的山区HHA的住院率和急诊室就诊率高于其他地区。
    结论:本研究强调了家庭医疗质量方面持续存在的城乡差距。该分析强调,持续需要采取有针对性的干预措施,以解决家庭医疗保健提供方面的差距,并确保城乡地区公平获得优质护理。我们的发现有可能为政策和实践提供信息,促进长期护理系统的公平和效率,为了更好的健康结果在整个美国。
    Urban-rural disparities in medical care, including in home healthcare, persist globally. With aging populations and medical advancements, demand for home health services rises, warranting investigation into home healthcare disparities. Our study aimed to (i) investigate the impact of rurality on home healthcare quality, and (ii) assess the temporal disparities and the changes in disparities in home healthcare quality between urban and rural home health agencies (HHAs), incorporating an analysis of geospatial distribution to visualize the underlying patterns. This study analyzed data from HHAs listed on the Centers for Medicare and Medicaid Services website, covering the period from 2010 to 2022. Data were classified into urban and rural categories for each HHA. We employed panel data analysis to examine the impact of rurality on home healthcare quality, specifically focusing on hospital admission and emergency room (ER) visit rates. Disparities between urban and rural HHAs were assessed using the Wilcoxon test, with results visualized through line and dot plots and heat maps to illustrate trends and differences comprehensively. Rurality is demonstrated as the most significant variable in hospital admission and ER visit rates in the panel data analysis. Urban HHAs consistently exhibit significantly lower hospital admission rates and ER visit rates compared to rural HHAs from 2010 to 2022. Longitudinally, the gap in hospital admission rates between urban and rural HHAs is shrinking, while there is an increasing gap in ER visit rates. In 2022, HHAs in Mountain areas, which are characterized by a higher proportion of rural regions, exhibited higher hospital admission and ER visit rates than other areas. This study underscores the persistent urban-rural disparities in home healthcare quality. The analysis emphasizes the ongoing need for targeted interventions to address disparities in home healthcare delivery and ensure equitable access to quality care across urban and rural regions. Our findings have the potential to inform policy and practice, promoting equity and efficiency in the long-term care system, for better health outcomes throughout the USA.
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  • 文章类型: Journal Article
    目的:回肠是克罗恩病(CD)中最常见的胃肠道病变。我们的目的是确定疾病位置是否影响对filgotinib的反应,Janus激酶(JAK)抑制剂,在中度至重度活动性克罗恩病(CD)患者中,并应用适当的方法来解释回肠与结肠相比在测量疾病活动方面的差异。
    方法:对来自FITZROY2期试验(NCT02048618)的数据进行事后分析,比较了回肠显性和孤立性结肠CD患者的克罗恩病活动指数(CDAI)和克罗恩病的简单内窥镜评分(SES-CD)的变化,这些患者接受了每天200mg菲尔戈替尼或安慰剂治疗10周。使用重复测量的混合效应模型来测试回肠疾病的反应是否与结肠疾病不同。通过使用治疗分配-疾病位置的相互作用项评估效果修改。
    结果:与回肠显性CD相比,孤立性结肠疾病患者的数量比例更大(CDAI<150,75.9%vs.41.6%)和内窥镜反应(SES-CD减少50%,52.5%vs.15.5%)在第10周。然而,在根据疾病位置和患者内聚类效应调整基线疾病活动后,不同疾病位置的治疗反应没有显着差异(回肠优势与之间ΔCDAI的平均差异孤立性结肠疾病+9.24[95%CI:-87.19,+105.67],p=0.85;ΔSES-CD的平均差-1.93[95%CI:-7.03,+3.44],p=0.48)。
    结论:在控制基线疾病活动性和聚集效应时,Filgotinib在回肠显性和孤立结肠CD中表现出相似的疗效。
    OBJECTIVE: The ileum is the most commonly affected segment of the gastrointestinal tract in Crohn\'s disease (CD). We aimed to determine whether disease location affects response to filgotinib, a Janus kinase (JAK) inhibitor, in patients with moderate-to-severely active Crohn\'s disease (CD) and applying appropriate methods to account for differences in measuring disease activity in the ileum compared to the colon.
    METHODS: This post-hoc analysis of data from the FITZROY phase 2 trial (NCT02048618) compared changes in the Crohn\'s Disease Activity Index (CDAI) and Simple Endoscopic Score for Crohn\'s Disease (SES-CD) amongst patients with ileal-dominant and isolated colonic CD treated with 10 weeks of filgotinib 200 mg daily or placebo. A mixed effects model for repeated measures was used to test whether ileal disease responded differently than colonic disease, by evaluating for effect modification using the interaction term of treatment assignment-by-disease location.
    RESULTS: Numerically greater proportions of patients with isolated colonic disease compared to ileal-dominant CD achieved clinical remission (CDAI <150, 75.9% vs. 41.6%) and endoscopic response (SES-CD reduction by 50%, 52.5% vs. 15.5%) at Week 10. However, after adjusting for baseline disease activity by disease location and within-patient clustering effects, there was no significant difference in treatment response by disease location (mean difference in ΔCDAI between ileal-dominant vs. isolated colonic disease +9.24 [95% CI: -87.19, +105.67], p=0.85; mean difference in ΔSES-CD -1.93 [95% CI: -7.03, +3.44], p=0.48).
    CONCLUSIONS: Filgotinib demonstrated similar efficacy in ileal-dominant and isolated colonic CD when controlling for baseline disease activity and clustering effects.
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  • 文章类型: Journal Article
    目的:在大多数低收入和中等收入国家(LMICs),乙酸目视检查(VIA)是一种低成本的宫颈癌筛查方法,但是,类似于其他视觉测试,是主观的,需要持续的培训和质量保证。我们开发了,受过训练,并验证了基于人工智能的“自动视觉评估”(AVE)工具,该工具可适用于在智能手机上运行,以评估智能手机捕获的子宫颈图像并识别癌前病变,帮助提高VIA性能。
    方法:前瞻性研究。
    方法:赞比亚的8个公共卫生设施。
    方法:共8204名25-55岁女性。
    方法:在常用的低成本智能手机模型上捕获的宫颈图像与关键临床信息相匹配,包括人类免疫缺陷病毒(HIV)和人乳头瘤病毒(HPV)状态,加上组织病理学分析(如适用),开发和训练AVE算法,并评估其性能,以用作HPV阳性女性的主要筛查和分诊测试。
    方法:受试者工作曲线下面积(AUC);灵敏度;特异性。
    结果:作为宫颈癌前病变的一般人群筛查工具,AVE识别的宫颈癌前病变和癌(CIN2+)病变具有高性能(AUC=0.91,95%置信区间[CI]=0.89-0.93),基于最大化Youden指数,其灵敏度为85%(95%CI=81%-90%),特异性为86%(95%CI=84%-88%)。这代表了一个相当大的改进,比肉眼直视,根据世界卫生组织(WHO)的荟萃分析,其敏感性为66%,特异性为87%。对于感染艾滋病毒的妇女来说,AVE的AUC为0.91(95%CI=0.88-0.93),在高危HPV检测呈阳性的人群中,AUC为0.87(95%CI=0.83-0.91)。
    结论:这些结果证明了在筛查计划中使用护士使用常用智能手机捕获的图像上使用AVE的可行性,并支持我们正在进行的努力,以更广泛地评估AVE的临床敏感性,特异性,可行性,以及在更广泛的环境中的可接受性。这项研究的局限性包括由于验证偏差而导致的性能估计的潜在膨胀(因为活检仅来自可见的aceto-white宫颈病变的参与者),并且由于这是内部验证(测试数据,虽然独立于用于开发算法的算法来自同一研究)。
    OBJECTIVE: Visual inspection with acetic acid (VIA) is a low-cost approach for cervical cancer screening used in most low- and middle-income countries (LMICs) but, similar to other visual tests, is subjective and requires sustained training and quality assurance. We developed, trained, and validated an artificial-intelligence-based \"Automated Visual Evaluation\" (AVE) tool that can be adapted to run on smartphones to assess smartphone-captured images of the cervix and identify precancerous lesions, helping augment VIA performance.
    METHODS: Prospective study.
    METHODS: Eight public health facilities in Zambia.
    METHODS: A total of 8204 women aged 25-55.
    METHODS: Cervical images captured on commonly used low-cost smartphone models were matched with key clinical information including human immunodeficiency virus (HIV) and human papillomavirus (HPV) status, plus histopathology analysis (where applicable), to develop and train an AVE algorithm and evaluate its performance for use as a primary screen and triage test for women who are HPV positive.
    METHODS: Area under the receiver operating curve (AUC); sensitivity; specificity.
    RESULTS: As a general population screening tool for cervical precancerous lesions, AVE identified cases of cervical precancerous and cancerous (CIN2+) lesions with high performance (AUC = 0.91, 95% confidence interval [CI] = 0.89-0.93), which translates to a sensitivity of 85% (95% CI = 81%-90%) and specificity of 86% (95% CI = 84%-88%) based on maximizing the Youden\'s index. This represents a considerable improvement over naked eye VIA, which as per a meta-analysis by the World Health Organization (WHO) has a sensitivity of 66% and specificity of 87%. For women living with HIV, the AUC of AVE was 0.91 (95% CI = 0.88-0.93), and among those testing positive for high-risk HPV types, the AUC was 0.87 (95% CI = 0.83-0.91).
    CONCLUSIONS: These results demonstrate the feasibility of utilizing AVE on images captured using a commonly available smartphone by nurses in a screening program, and support our ongoing efforts for moving to more broadly evaluate AVE for its clinical sensitivity, specificity, feasibility, and acceptability across a wider range of settings. Limitations of this study include potential inflation of performance estimates due to verification bias (as biopsies were only obtained from participants with visible aceto-white cervical lesions) and due to this being an internal validation (the test data, while independent from that used to develop the algorithm was drawn from the same study).
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  • 文章类型: Journal Article
    镉(Cd)是一种在土壤和农作物中发现的重金属和天然元素,其浓度与施用到农田的磷肥和污水污泥有关。大部分美国老年男性和女性都记录了Cd暴露。镉暴露已经证明了健康问题,例如吸入肺癌的风险和肾功能受损;然而,越来越多的证据表明,它也会影响骨骼和肌肉的健康。鉴于低水平的镉可能会影响骨骼和肌肉,我们利用美国对老年男性和女性骨健康的两项最大和最详细的研究设计了前瞻性研究:男性骨质疏松性骨折研究和骨质疏松性骨折研究.我们正在调查尿镉(U-Cd)的关联,作为长期镉暴露的替代品,骨骼和肌肉健康。从机械和横断面研究中建立暗示性证据,这将是第一个对意外骨折结果进行有力的前瞻性研究,骨丢失,与U-Cd相关的肌肉损失,已建立的长期Cd暴露的生物标志物。以下是预期研究的拟议方案;如果成功,拟议的研究可能会对指导美国未来减少美国人口中Cd暴露的政策产生影响,类似于欧盟最近采取的限制肥料中Cd的政策。
    Cadmium (Cd) is a heavy metal and natural element found in soil and crops with increasing concentrations linked to phosphate fertilizers and sewage sludge applied to crop lands. A large fraction of older US men and woman have documented Cd exposure. Cd exposure has proven health concerns such as risk of lung cancer from inhalation and impaired renal function; however, growing evidence suggests it also influences bone and muscle health. Given that low levels of Cd could affect bone and muscle, we have designed prospective studies using the two largest and most detailed US studies of bone health in older men and women: the Osteoporotic Fractures in Men Study and the Study of Osteoporotic Fractures. We are investigating the association of urinary cadmium (U-Cd), as a surrogate for long-term Cd exposure, with bone and muscle health. Building off suggestive evidence from mechanistic and cross-sectional studies, this will be the first well-powered prospective study of incident fracture outcomes, bone loss, and muscle loss in relation to U-Cd, an established biomarker of long-term Cd exposure. The following is a proposed protocol for the intended study; if successful, the proposed studies could be influential in directing future US policy to decrease Cd exposure in the US population similar to recent policies adopted by the European Union to limit Cd in fertilizers.
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  • 文章类型: Meta-Analysis
    背景:当随机化可能不可行时,中断时间序列(ITS)是评估公共卫生和政策干预或暴露的强大设计。有几种统计方法可用于ITS研究的分析和荟萃分析。当应用于现实世界的ITS数据时,我们试图从经验上比较可用的方法。
    方法:我们从已发布的元分析中获取ITS数据,以创建在线数据存储库。使用两种ITS估计方法重新分析每个数据集。使用固定效应和四种随机效应荟萃分析方法计算并组合了水平和斜率变化效应估计值(和标准误差)。我们检查了荟萃分析水平和斜率变化估计值的差异,他们95%的置信区间,p值,以及统计方法对异质性的估计。
    结果:在40个合格的荟萃分析中,我们获得了17项荟萃分析的数据,包括282项ITS研究(主要调查公共卫生中断的影响(88%)),并进行了分析.我们发现平均而言,元分析效应估计,他们的标准误差和研究间差异对荟萃分析方法的选择不敏感,与ITS分析方法无关。然而,在整个ITS分析方法中,对于任何给定的荟萃分析,元分析效应估计可能存在小到中等的差异,和荟萃分析标准误差的重要差异。此外,meta分析效应估计值的置信区间宽度和p值根据置信区间方法和ITS分析方法的选择而变化.
    结论:我们的实证研究表明,荟萃分析效应估计,他们的标准误差,置信区间宽度和p值可能受统计方法选择的影响。这些差异可能会影响荟萃分析的解释和结论,并表明统计方法在实践中不可互换。
    BACKGROUND: The Interrupted Time Series (ITS) is a robust design for evaluating public health and policy interventions or exposures when randomisation may be infeasible. Several statistical methods are available for the analysis and meta-analysis of ITS studies. We sought to empirically compare available methods when applied to real-world ITS data.
    METHODS: We sourced ITS data from published meta-analyses to create an online data repository. Each dataset was re-analysed using two ITS estimation methods. The level- and slope-change effect estimates (and standard errors) were calculated and combined using fixed-effect and four random-effects meta-analysis methods. We examined differences in meta-analytic level- and slope-change estimates, their 95% confidence intervals, p-values, and estimates of heterogeneity across the statistical methods.
    RESULTS: Of 40 eligible meta-analyses, data from 17 meta-analyses including 282 ITS studies were obtained (predominantly investigating the effects of public health interruptions (88%)) and analysed. We found that on average, the meta-analytic effect estimates, their standard errors and between-study variances were not sensitive to meta-analysis method choice, irrespective of the ITS analysis method. However, across ITS analysis methods, for any given meta-analysis, there could be small to moderate differences in meta-analytic effect estimates, and important differences in the meta-analytic standard errors. Furthermore, the confidence interval widths and p-values for the meta-analytic effect estimates varied depending on the choice of confidence interval method and ITS analysis method.
    CONCLUSIONS: Our empirical study showed that meta-analysis effect estimates, their standard errors, confidence interval widths and p-values can be affected by statistical method choice. These differences may importantly impact interpretations and conclusions of a meta-analysis and suggest that the statistical methods are not interchangeable in practice.
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  • 文章类型: Journal Article
    在晚发性庞贝病患者的COMET试验中,用α-葡糖苷酶(AVA)和α-葡糖苷酶(ALGLU)观察到直立用力肺活量(FVC)预测%的改善(估计治疗差异:2.43%).预先指定的混合模型重复测量(MMRM)分析显示AVA的非劣效性(P=0.0074)和狭窄的优势(P=0.063;95%CI:-0.13-4.99)。我们在两个事后分析中报告了AVA的优越性,这些分析解释了基线时FVC低和严重慢性阻塞性肺疾病的极端异常参与者:MMRM排除异常(P=0.013)和所有数据的非参数分析与重复测量协方差分析(P=0.019)。
    In the COMET trial of patients with late-onset Pompe disease, greater improvement in upright forced vital capacity (FVC) % predicted was observed with avalglucosidase alfa (AVA) vs alglucosidase alfa (ALGLU) (estimated treatment difference: 2.43%). The pre-specified mixed model repeated measures (MMRM) analysis demonstrated non-inferiority of AVA (P = 0.0074) and narrowly missed superiority (P = 0.063; 95% CI: -0.13-4.99). We report superiority of AVA in two post-hoc analyses that account for an extreme outlier participant with low FVC and severe chronic obstructive pulmonary disease at baseline: MMRM excluding the outlier (P = 0.013) and non-parametric analysis of all data with repeated measures analysis of covariance (P = 0.019).
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  • 文章类型: Journal Article
    背景:产科护理是开发和应用预后预测模型的一个高度活跃的领域。这些模型的开发和验证通常需要使用先进的统计技术。然而,不遵守严格的方法标准可能会极大地损害结果模型的可靠性和可信性。因此,我们研究的目的是研究目前产科护理中采用的统计方法,并提出建议,以提高统计方法在预后预测模型开发中的应用.
    方法:我们使用10年(2011-2020年)发表的开发或验证产科护理预后预测模型的研究样本进行了横断面调查。编制了结构化问卷,调查了五个领域的统计问题,包括模型推导(预测器选择和算法开发),模型验证(内部和外部),模型性能,模型演示,和风险阈值设置。根据调查结果和现有准则,我们制定了预后模型中统计方法的推荐列表.
    结果:共纳入112项符合条件的研究,有107个报告模型开发和5个独家报告外部验证。在模型开发过程中,58.9%的研究没有包括任何形式的验证。其中,46.4%以粗略的方式使用逐步回归进行预测因子选择,而三分之二的人只根据p值决定保留或删除候选预测因子。此外,26.2%将连续预测因子转化为分类变量,80.4%没有考虑预测因子和结果之间的非线性关系。令人惊讶的是,94.4%的研究没有检查预测因子之间的相关性。此外,47.1%的研究没有比较开发和外部验证数据集之间的人群特征,只有五分之一的人评估了辨别和校准。此外,53.6%的研究没有清楚地展示模型,不到一半的人建立了风险阈值来定义风险类别。根据这些发现,提出了10项建议,以促进适当使用统计方法。
    结论:统计方法的使用还不是最佳的。提供了十项建议,以协助产科护理中预后预测模型的统计方法。
    BACKGROUND: Obstetric care is a highly active area in the development and application of prognostic prediction models. The development and validation of these models often require the utilization of advanced statistical techniques. However, failure to adhere to rigorous methodological standards could greatly undermine the reliability and trustworthiness of the resultant models. Consequently, the aim of our study was to examine the current statistical practices employed in obstetric care and offer recommendations to enhance the utilization of statistical methods in the development of prognostic prediction models.
    METHODS: We conducted a cross-sectional survey using a sample of studies developing or validating prognostic prediction models for obstetric care published in a 10-year span (2011-2020). A structured questionnaire was developed to investigate the statistical issues in five domains, including model derivation (predictor selection and algorithm development), model validation (internal and external), model performance, model presentation, and risk threshold setting. On the ground of survey results and existing guidelines, a list of recommendations for statistical methods in prognostic models was developed.
    RESULTS: A total of 112 eligible studies were included, with 107 reporting model development and five exclusively reporting external validation. During model development, 58.9% of the studies did not include any form of validation. Of these, 46.4% used stepwise regression in a crude manner for predictor selection, while two-thirds made decisions on retaining or dropping candidate predictors solely based on p-values. Additionally, 26.2% transformed continuous predictors into categorical variables, and 80.4% did not consider nonlinear relationships between predictors and outcomes. Surprisingly, 94.4% of the studies did not examine the correlation between predictors. Moreover, 47.1% of the studies did not compare population characteristics between the development and external validation datasets, and only one-fifth evaluated both discrimination and calibration. Furthermore, 53.6% of the studies did not clearly present the model, and less than half established a risk threshold to define risk categories. In light of these findings, 10 recommendations were formulated to promote the appropriate use of statistical methods.
    CONCLUSIONS: The use of statistical methods is not yet optimal. Ten recommendations were offered to assist the statistical methods of prognostic prediction models in obstetric care.
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  • 文章类型: Journal Article
    目的:以重复测量连续变量作为主要结局的随机对照试验(RCT)很常见。尽管在此类试验中计算样本量的统计方法已经得到了广泛的研究,其实际应用尚不清楚。本研究旨在概述不同研究问题的样本量计算方法(例如,关键时间点治疗效果,治疗效果随时间的变化),并评估试验设计中当前实践的充分性。
    方法:我们对PubMed进行了全面搜索,以确定2019年在核心期刊上发表的RCT,这些RCT利用重复测量的连续变量作为其主要结果。使用预定义的问卷提取数据,包括一般研究特征,主要结果,详细的样本量计算方法,和分析主要结果的方法。我们重新估计了提供所有相关参数的试验的样本量。
    结果:共纳入168项随机对照试验,每个结果的中位数为四次重复测量(四分位距3-6)。在48项(28.6%)试验中,用于样本量计算的主要结局与用于定义主要结局的主要结局不同.有90项(53.6%)试验显示指定用于样本量计算的假设与指定用于主要分析的假设之间存在不一致。在158(94.0%)个试验中用于样本量计算的统计方法与用于主要分析的方法不一致。此外,只有6项(3.6%)试验占重复测量的数量,和7(4.2%)试验在计算样本量时考虑了这些测量之间的相关性。此外,在128项(76.2%)考虑随访失败的试验中,33(25.8%)使用了错误的公式(即,样本大小调整的N*(1+损失率)。在107项试验中的53项(49.5%),重新估计的样本量大于报告的样本量.
    结论:以重复测量的连续变量作为主要结果的RCT的样本量计算实践显示出明显的缺陷,相当比例的试验未能报告样本量计算所需的重复测量的基本参数.我们的发现强调了迫切需要使用与研究假设一致的最佳样本量方法,初级分析方法,以及主要结果的形式。
    OBJECTIVE: Randomized controlled trials (RCTs) with repeatedly measured continuous variables as primary outcomes are common. Although statistical methodologies for calculating sample sizes in such trials have been extensively investigated, their practical application remains unclear. This study aims to provide an overview of sample size calculation methods for different research questions (e.g., key time point treatment effect, treatment effect change over time) and evaluate the adequacy of current practices in trial design.
    METHODS: We conducted a comprehensive search of PubMed to identify RCTs published in core journals in 2019 that utilized repeatedly measured continuous variables as their primary outcomes. Data were extracted using a predefined questionnaire including general study characteristics, primary outcomes, detailed sample size calculation methods, and methods for analyzing the primary outcome. We re-estimated the sample size for trials that provided all relevant parameters.
    RESULTS: A total of 168 RCTs were included, with a median of four repeated measurements (interquartile range 3-6) per outcome. In 48 (28.6%) trials, the primary outcome used for sample size calculation differed from the one used in defining the primary outcomes. There were 90 (53.6%) trials exhibited inconsistencies between the hypotheses specified for sample size calculation and those specified for primary analysis. The statistical methods used for sample size calculation in 158 (94.0%) trials did not align with those used for primary analysis. Additionally, only 6 (3.6%) trials accounted for the number of repeated measurements, and 7 (4.2%) trials considered the correlation among these measurements when calculating the sample size. Furthermore, of the 128 (76.2%) trials that considered loss to follow-up, 33 (25.8%) used an incorrect formula (i.e., N∗(1+lose rate) for sample size adjustment. In 53 (49.5%) out of 107 trials, the re-estimated sample size was larger than the reported sample size.
    CONCLUSIONS: The practice of sample size calculation for RCTs with repeatedly measured continuous variables as primary outcomes displayed significant deficiencies, with a notable proportion of trials failed to report essential parameters about repeated measurement required for sample size calculation. Our findings highlight the urgent need to use optimal sample size methods that align with the research hypothesis, primary analysis method, and the form of the primary outcome.
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  • 文章类型: Journal Article
    Denosumab(Dmab)在全球范围内越来越多。与双膦酸盐(BPs)不同,它对死亡率的影响还有待充分探索。这项研究检查了Dmab与全因死亡率之间的关系,与没有骨折的受试者中没有治疗相比。研究人群来自萨克斯研究所的45及以上研究(n=267,357),一个前瞻性的基于人群的队列,问卷数据与医院入院1相关,用药记录2和存储安全3。实施了具有倾向评分(PS)匹配的新用户队列设计。在骨折队列中,Dmab和口服BP使用者匹配1:2,不治疗(Dmab:617名女性,154人,和口服BPs:615名女性,266名男子)。在无骨折队列中,Dmab使用者与口服BPs和唑来膦酸(Zol)使用者1:1匹配(Dmab:口服BPs-479名男性,1534名女性和Dmab:Zol-280名男性,625名妇女)。使用性别特异性配对多变量Cox模型测量死亡率风险。在骨折队列中,与没有治疗相比,Dmab与女性死亡率降低48%相关(HR0.52;95%CI,0.36-0.72),但与男性无关。口服BP与男女死亡率降低44%相关(女性HR0.56;95%CI,0.42-0.77,男性HR0.56;95%CI,0.40-0.78)。在无骨折队列中,与BP相比,Dmab的死亡率比口服BP高1.5至2.5倍(女性HR1.49;95%CI,1.13-1.98,男性HR2.74;95%CI,1.82-4.11),但死亡率与Zol相似。女性Dmab和口服BPs与骨折后死亡率低于不治疗相关。然而,在没有骨折的患者中,Dmab使用者的死亡率通常高于口服BP使用者。本文受版权保护。保留所有权利。
    Denosumab (Dmab) is increasingly prescribed worldwide. Unlike bisphosphonates (BPs), its effect on mortality has yet to be well explored. This study examined the association between Dmab and all-cause mortality compared with no treatment in subjects with a fracture and BPs in subjects without a fracture. The study population was from the Sax Institute\'s 45 and Up Study (n = 267,357), a prospective population-based cohort with questionnaire data linked to hospital admissions (Admitted Patients Data Collection [APDC] data were linked by the Centre for Health Record Linkage), medication records (Pharmaceutical Benefits Scheme [PBS] provided by Services Australia), and stored securely (secure data access was provided through the Sax Institute\'s Secure Unified Research Environment [SURE]). The new-user cohort design with propensity-score (PS) matching was implemented. In the fracture cohort, Dmab and oral BP users were matched 1:2 to no treatment (Dmab: 617 women, 154 men; oral BPs: 615 women, 266 men). In the no-fracture cohort, Dmab users were matched 1:1 with oral BPs and zoledronic acid (Zol) users (Dmab:oral BPs: 479 men, 1534 women; Dmab:Zol: 280 men, 625 women). Mortality risk was measured using sex-specific pairwise multivariable Cox models. In the fracture cohort, compared with no treatment, Dmab was associated with 48% lower mortality in women (hazard ratio [HR] = 0.52, 95% confidence interval [CI] 0.36-0.72) but not in men. Oral BPs were associated with 44% lower mortality in both sexes (women HR = 0.56, 95% CI 0.42-0.77; men HR = 0.56, 95% CI 0.40-0.78). In the no-fracture cohort, compared with BPs, Dmab was associated with 1.5- to 2.5-fold higher mortality than oral BPs (women HR = 1.49, 95% CI 1.13-1.98; men HR = 2.74; 95% CI 1.82-4.11) but similar mortality to Zol. Dmab in women and oral BPs were associated with lower post-fracture mortality than no treatment. However, Dmab users had generally higher mortality than oral BP users in those without fractures. © 2023 American Society for Bone and Mineral Research (ASBMR).
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  • 文章类型: Journal Article
    跨越宽带的水下声景显示出与贡献噪声源和海洋环境一致的可变性。然而,人为活动的增加会导致噪声扩散,从而损害自然海洋栖息地。背景声音的连续监测对于评估声景的这种时空变化是有用的。标准噪声水平指标,例如,平均值(μ),第90个百分位数(90P),标准偏差(σ),和峰度(β),由阿拉伯海东部三个沿海站测量的噪声场构成。发现这些度量适合描述相对于季节的声景变化,频率,和深度。平均值和90P用于比较季节性变化,同时使用峰度度量来检查复合信号的脉冲性质。利用直方图表示和概率密度函数(PDF)来分析音景相对于季节的频谱变化。在与交通和风噪声场相对应的两个光谱带中,以500毫秒的时间窗口进行了分析。季节分析表明,在夏季,平均噪声水平随着水听器深度的增加而降低,而在冬天,随着季节性表面管道的存在,更深的深度具有更高的平均值。使用适当的噪声模型也证实了声速分布对噪声场的这种含义。
    Underwater soundscape that spans a broad frequency band shows variability consistent with contributing noise sources and ocean environment. However, increased anthropogenic activities result in noise proliferation which can harm natural marine habitat. Continuous monitoring of background sound is useful to assess such spatio-temporal variability of soundscape. Standard noise level metrics, for instance, mean (μ), 90th percentiles (90P), standard deviation (σ), and kurtosis (β), are constructed from noise field measured from three coastal stations in Eastern Arabian Sea. These metrics are found to be suitable to describe the soundscape variability with respect to season, frequency, and depth. Mean and 90P are used to compare the seasonal variations while kurtosis metrics are exercised to check the impulsive nature of composite signal. Histogram representation and probability density function (PDF) were utilized to analyze the spectral variation in soundscape with respect to season. Analysis was carried out at 500-ms temporal window in two spectral bands corresponding to traffic and wind noise fields. Seasonal analysis shows that in summer, mean noise level decreases as hydrophone depth increases, while in winter, deeper depths have higher mean value with the presence of seasonal surface duct. This implication of sound speed profile on noise field has also been confirmed using appropriate noise model.
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