调查点不足偏倚对疾病空间分布趋势面分析结果的影响

[目的]探讨调查点不足偏倚对趋势面分析结果的影响。[方法]以基准面为基础，在保证调查点分布均匀化的前提下，依次减少调查点个数，并拟合同阶趋势面模型，观察模型的趋势等值线图和剩余等值线图，评价随调查点的递减，趋势面形态的变化情况。[结果]随调查点数的递减，趋势等值线图的偏倚较小，但剩余等值线图的偏倚严重。[结论]当用趋势面模型反映疾病发病水平在大尺度范围内的空问变化趋势时，用较少的调查点就能反映出来，不至于发生严重偏倚，但调查点数必须大于多项式的项数；当用趋势面模型寻找有地理流行病学意义的异常区域时，调查点太少会发生严重偏倚。     

疾病空间分布趋势面模型的共线性偏倚及其测量与控制

目的探讨趋势面分析中共线性偏倚及其测量与控制方法.方法以疾病监测资料为基础,引用回归诊断方法识别趋势面模型的共线性偏倚,进一步用岭回归趋势面模型控制共线性偏倚.结果趋势面分析往往存在共线性偏倚,利用岭回归趋势面分析可以在一定程度上控制共线性偏倚.结论在作趋势面分析时应当考虑共线性偏倚对结果的影响,并设法予以控制.     

应用趋势面模型分析传染性疾病的地理分布趋势

目的应用趋势面模型分析传染性疾病的地理分布趋势。方法以多元回归分析理论为基础，构造趋势面回归数学模型，并依据模型方程绘制趋势面层次分析图。结果获得对传染性疾病地理分布进行监测的定量方法。结论该方法可用于分析疾病地理分布系统和局部变异情况，并可直观地表示不同地理位置疾病严重程度的变化状况，可作为探讨传染性疾病地理流行病学发病机制的有效工具。     

趋势面分析在地理流行病学中的应用

趋势面分析在地理流行病学中的应用丁愈，魏善波地理流行病学是近年发展起来的流行病学分支，它是用地理学观点和方法解决有关医学问题［１］。本文试以在地质学和其他学科普遍应用的趋势面分析法进行地理流行病学研究，将地理位置上有一定分布特征的研究对象划分成两部分...     

用趋势面分析法研究我国涂阳肺结核患病率的地理分布

采用趋势面分析方法，对我国１９７９、１９９０年两次流行病学调查所获得的涂阳肺结核患病率资料进行研究。结果表明，我国的涂阳肺结核患病率有一定的地理分布特点，通过１１年的结防工作，分布特点也发生了改变。总的来看患病率的分布与各地多年来的防治工作质量相吻合。     

广西霍乱地理流行病学特征的趋势面研究

目的了解广西霍乱流行的地理分布特征及地理趋势。方法采用趋势面分析方法 ,建立趋势面数学模型 ,对广西1961～1999年霍乱累计发病率资料进行分析。结果发病率在经度108°～109°、纬度22°区域最高,在纬度25°的北部形成另三个高峰,在经度108°～109°带宽上其等值线变化频率最大。结论广西霍乱流行呈现四个地理趋势高峰值 ,以沿海地区发病率最高 ,其次为北部山区 ,流行趋势由南至北向内陆扩散 ,在经度108°～109°区域对地理位置的变化最具敏感性。     

应用趋势面分析探索食管癌死亡率的地理分布特征

[目的]应用趋势面分析法，探讨福建省食管癌地理分布特征及分布趋势，为病因学研究提供线索。[方法]采用趋势面分析法，建立趋势面函数，对福建省1973—1975年食管癌死亡率资料进行研究。[结果]应用二阶趋势面函数能描述福建省食管癌死亡率的地理分布规律性(拟合优度为64．3％)，死亡率高的县市都集中在东南沿海，而闽西北山区死亡率低，并有从南向北呈梯度分布的特点。[结论]福建省食管癌死亡率具有明显的地区分布特征，表明地理环境因素在食管癌的发生发展过程中具有一定作用。     

山东省胃癌死亡率地域分布的趋势面分析

<正> 趋势面分析可以弥补描述疾病地域分布的统计地图法的不足。各种统计地图法只能描述每个地区的实际发病率或死亡率,不能定量分析发病率或死亡率是否存在空间趋势性及趋势性的大小和局部异常及其地理流行病学意义;而趋势面分析是以多元回归分析为基础的一种统计分析方法,能够安准确的反映疾病总的空间分布规律,从而为胃癌等疾病死亡率的区域差异提供了新的研究技术和方法。     

恶性肿瘤死亡率地域分布的趋势面分析

目的 研究主要恶性肿瘤死亡率的地域分布有无规律性,为下一步寻找病因,为政府制定干预措施提供理论依据.方法 利用山东省某县主要恶性肿瘤死亡率资料,进行地域趋势面分析.结果 胃癌和鼻咽癌死亡率的分布有明显的地域规律性.其中,胃癌死亡率在该县呈由西向东逐渐增高,鼻咽癌则呈现由西向东逐渐降低的趋势.另外,有些地区的剩余值明显高于(或低于)剩余界值,呈现出规律外的特殊性.结论 胃癌、鼻咽癌死亡率在山东省某县内有地域差异,应进一步研究具体生活习惯、经济状况等因素的差异及与相关肿瘤的关系,对于存在异常剩余值的地区,应作为重点研究对象,探讨这些地区可能存在的某种肿瘤保护或危险因素.     

趋势面分析法研究我国足月低体重儿地理特征

本文介绍了趋势面分析方法,并将其应用于我国足月低体重儿地理分布的研究。结果表明,三阶趋势面方程能解释观察变异的86.32％,可较好地描述足月低体重儿的地理分布规律。足月低体重儿具有明显的地理分布特征,其发生率以北部、东部和东北部较低,西南部较高。提示地理环境等因素在足月低体重几发生中可能起着重要作用。     

医用工程地面装饰分项的选材及施工要点

随着广大患者对就医环境要求的日益提高,医用工程装饰、装修的标准也在不断变化。医用工程地面装饰用材料应按照各部位特殊要求而具体设定,从走道到候诊室,从治疗室到手术室,从普通病房到特殊病房,从内部使用区域到外部使用区域,选择不同功能的产品,才能达到最佳效果。     

上海市短缺药品特点及使用变化情况研究

目的:分析2016—2018年上海市短缺药品特点和使用变化情况,为短缺药供应保障和动态监测提供思路和方法。方法:通过描述性统计分析,并应用拉式指数和帕式指数判断短缺药品价格和用量变化趋势和变化幅度。结果:2016—2018年上海市短缺药品主要为医保目录内药品,分布在不同治疗领域,以心血管系统药物短缺品种居多,以液体制剂为主,主要涉及价格较低的药品;短缺药品价格和用量整体呈上升趋势,但用药结构发生变化,主要表现在高价短缺药品用量减少,低价短缺药品用量增加。结论:整体来看,上海市在短缺药品价格小幅上升的基础上较好地保障了供应需求,应加强对短缺药品价格和用量的长期动态监测,保障药品供应,降低群众用药负担。     

Causal Modeling to Mitigate Selection Bias and Unmeasured Confounding in Internet-Based Epidemiology of COVID-19: Model Development and Validation

BackgroundSelection bias and unmeasured confounding are fundamental problems in epidemiology that threaten study internal and external validity. These phenomena are particularly dangerous in internet-based public health surveillance, where traditional mitigation and adjustment methods are inapplicable, unavailable, or out of date. Recent theoretical advances in causal modeling can mitigate these threats, but these innovations have not been widely deployed in the epidemiological community.ObjectiveThe purpose of our paper is to demonstrate the practical utility of causal modeling to both detect unmeasured confounding and selection bias and guide model selection to minimize bias. We implemented this approach in an applied epidemiological study of the COVID-19 cumulative infection rate in the New York City (NYC) spring 2020 epidemic.MethodsWe collected primary data from Qualtrics surveys of Amazon Mechanical Turk (MTurk) crowd workers residing in New Jersey and New York State across 2 sampling periods: April 11-14 and May 8-11, 2020. The surveys queried the subjects on household health status and demographic characteristics. We constructed a set of possible causal models of household infection and survey selection mechanisms and ranked them by compatibility with the collected survey data. The most compatible causal model was then used to estimate the cumulative infection rate in each survey period.ResultsThere were 527 and 513 responses collected for the 2 periods, respectively. Response demographics were highly skewed toward a younger age in both survey periods. Despite the extremely strong relationship between age and COVID-19 symptoms, we recovered minimally biased estimates of the cumulative infection rate using only primary data and the most compatible causal model, with a relative bias of +3.8% and –1.9% from the reported cumulative infection rate for the first and second survey periods, respectively.ConclusionsWe successfully recovered accurate estimates of the cumulative infection rate from an internet-based crowdsourced sample despite considerable selection bias and unmeasured confounding in the primary data. This implementation demonstrates how simple applications of structural causal modeling can be effectively used to determine falsifiable model conditions, detect selection bias and confounding factors, and minimize estimate bias through model selection in a novel epidemiological context. As the disease and social dynamics of COVID-19 continue to evolve, public health surveillance protocols must continue to adapt; the emergence of Omicron variants and shift to at-home testing as recent challenges. Rigorous and transparent methods to develop, deploy, and diagnosis adapted surveillance protocols will be critical to their success.     

孕晚期缺铁与婴儿缺铁性贫血相关性分析

目的探讨母亲孕晚期铁元素（Fe）缺乏与婴儿缺铁性贫血的的关系。方法对2007年1月1日-2008年1月1日在秦皇岛市妇幼保健院出生的4个月婴儿进行静脉血常规检查及微量元素检查;孕晚期母亲进行微量元素检查及问卷调查,了解贫血的发生情况。结果母亲孕晚期Fe缺乏101例,4个月婴儿缺铁性贫血93例;母亲孕晚期Fe正常363例,4个月婴儿缺铁性贫血85例,差异有统计学意义（P〈0．05）。结论孕晚期母亲Fe缺乏与婴儿缺铁性贫血有明显的相关性,重视孕晚期母亲Fe的补充可以预防婴儿缺铁性贫血。     

预测模型研究的偏倚风险和适用性评估工具解读

本文介绍了预测模型研究的偏倚风险和适用性评估工具PROBAST（Prediction model Risk Of Bias ASsessment Tool）的主要内容、评价步骤和相关注意事项。PROBAST从研究对象、预测因素、结局和分析4个领域共20个信号问题对原始研究的设计、实施和分析过程中可能产生的偏倚风险和适用性进行评价。通过综合分析，对原始研究每个领域和整体的偏倚风险和适用性做出判断，分为高、低或不清楚。PROBAST为个体预测模型开发、验证和更新提供了可靠的新评价工具，它不仅可以用于预测模型的系统综述，也可作为预测模型研究通用的方法学评价工具。     

趋势面和残差分析法在研究死亡水平地域分布中的应用

目的探讨趋势面分析法和残差分析法在研究死亡水平地域性分布特点中的应用. 方法趋势面分析法和残差分析法. 结果三阶趋势面方程合理地描述了地理位置与死亡水平的关系,解释了死亡变异的75.87%;对扣除地理因素后剩余24.13%的变异作残差分析,揭示出某些地区存在使死亡水平增高的危险因素,而在另一些地区存在使其下降的保护因素. 结论趋势面分析法和残差分析法相结合可以全面地分析各地区死亡水平的分布特征.     

A Meta-Epidemiological Study of Positive Results in Clinical Nutrition Research: The Good,the Bad and the Ugly of Statistically Significant Findings

Positive (statistically significant) findings are easily produced in nutrition research when specific aspects of the research design and analysis are not accounted for. To address this issue, recently, a pledge was made to reform nutrition research and improve scientific trust on the science, encompass research transparency and achieve reproducibility. The aim of the present meta-epidemiological study was to evaluate the statistical significance status of research items published in three academic journals, all with a focus on clinical nutrition science and assessing certain methodological/transparency issues. All research items were published between the years 2015 and 2019. Study design, primary and secondary findings, sample size and age group, funding sources, positivist findings, the existence of a published research protocol and the adjustment of nutrients/dietary indexes to the energy intake (EI) of participants, were extracted for each study. Out of 2127 studies in total, those with positive findings consisted of the majority, in all three journals. Most studies had a published research protocol, however, this was mainly due to the randomized controlled trials and not to the evidence-synthesis studies. No differences were found in the distribution of positive findings according to the existence/inexistence of a published research protocol. In the pooled sample of studies, positive findings differed according to study design and more significant findings were reported by researchers failing to report any funding source. The majority of items published in the three journals (65.9%) failed to account for the EI of participants. The present results indicate that there is still room for the improvement of nutrition research in terms of design, analyses and reporting.     

深圳市南山区2005—2016年淋病流行特征及ARIMA模型发病趋势预测

目的了解深圳市南山区淋病流行特征及发病趋势,为制定控制策略提供科学依据。方法对2005年1月-2016年12月深圳市南山区报告的淋病病例资料进行流行病学分析,并利用ARIMA模型进行发病趋势预测。结果深圳市南山区2005-2016年累计报告淋病9 590例,报告发病率波动在59.45/10万～102.74/10万,年均报告发病率为78.79/10万。年龄主要集中在20～45岁,占88.06%;职业以工人、干部职员和家务及待业为主,占70.23%。淋病月发病率波动在2.84/10万～10.56/10万。构建的ARIMA（1,1,1）模型,对深圳市南山区2017年淋病发病率进行预测,结果显示2017年1-5月深圳市南山区淋病预测发病率与实际发病率的波动形势基本一致,实际发病率略高于预测值,但均是在预测值的95%置信区间。结论该区淋病疫情较重,ARIMA模型能较精准地预测淋病的发病趋势,预测结果提示淋病的发病维持在较高水平,建议根据淋病流行特点采取有效的防治措施。     

Bias in the assessment of family history of melanoma and its association with dysplastic nevi in a case-control study

Family history of melanoma is an important risk factor for both melanoma and, it is thought, dysplastic nevi. However, assessment of family history of melanoma in epidemiologic investigations has typically been limited to interview of the proband. As part of a case-control study of dysplastic nevi, we attempted to confirm family histories. We disproved about half of the reported family histories of melanoma among first-degree relatives, and confirmed them by medical records in only 17%. Few family histories pertaining to other relatives could be confirmed. We documented the association of melanoma family history with dysplastic nevus risk, and we further documented a substantially greater odds ratio for this association when history was based on confirmation by medical records, compared to confirmation by proband interview only. The bias thus documented must be considered in evaluating the many published epidemiologic studies of melanoma and related disorders. Future research should attempt to confirm family histories of melanoma whenever possible, despite the practical difficulties.