Space–time clustering of case–control data with residential histories: insights into empirical induction periods, age-specific susceptibility, and calendar year-specific effects     

Jaymie R. Meliker  Geoffrey M. Jacquez 《Stochastic Environmental Research and Risk Assessment (SERRA)》2007,21(5):625-634

Our research group recently developed Q-statistics for evaluating space–time clustering in case–control studies with residential histories. This technique relies on time-dependent nearest-neighbor relationships to examine clustering at any moment in the life-course of the residential histories of cases relative to that of controls. In addition, in place of the widely used null hypothesis of spatial randomness, each individual’s probability of being a case is based instead on his/her risk factors and covariates. In this paper, we extend this approach to illustrate how alternative temporal orientations (e.g., years prior to diagnosis/recruitment, participant’s age, and calendar year) influence a spatial clustering pattern. These temporal orientations are valuable for shedding light on the duration of time between clustering and subsequent disease development (known as the empirical induction period), and for revealing age-specific susceptibility windows and calendar year-specific effects. An ongoing population-based bladder cancer case–control study is used to demonstrate this approach. Data collection is currently incomplete and therefore no inferences should be drawn; we analyze these data to demonstrate these novel methods. Maps of space–time clustering of bladder cancer cases are presented using different temporal orientations while accounting for covariates and known risk factors. This systematic approach for evaluating space–time clustering has the potential to generate novel hypotheses about environmental risk factors and provides insights into empirical induction periods, age-specific susceptibility, and calendar year-specific effects.  相似文献   

中国癌症与土壤环境中Er元素的关系   总被引：4，自引：2，他引：2  

曾昭华  曾雪萍 《吉林地质》2000,19(1):72-75

利用土壤环境中铒元素资料７６６个数据,癌死亡调查资料７８７ ０８０例,研究了胃癌 食管癌、肝癌、宫颈癌、肺癌、大肠癌、白血病、鼻咽癌、乳腺癌死亡率与人群生存区土壤环境中铒元素的关系。结果表明,仅癌死亡率与铒元素有相关性,等级相关系数为－０．５０６９（Ｐ〈０．００５）。  相似文献   

中国癌症与土壤环境中硼元素的关系   总被引：3，自引：1，他引：2  

曾昭华  曾雪萍 《四川地质学报》2000,20(2):136-139

研究了各种癌症死亡率与人群生存区土壤环境中硼元素的关系,结果表明,仅宫颈癌死亡率与硼元素有相关性,等级相关系数为－０．３１２５（Ｐ〈０．０５）。  相似文献   

条石鲷消化道发育的组织学观察     

马道远  于道德  肖永双  刘清华  徐世宏  李军  肖志忠 《海洋科学》2011,35(12):28-35

对人工养殖的条石鲷（Oplegnathus fasciatus）仔、幼稚鱼消化道及消化腺的发育过程进行了系统的组织学观察。研究表明： 初孵仔鱼 （体长1.66～2.20 mm）的消化道完全处于未分化状态。1 日龄仔鱼全长1.83～2.32 mm, 消化道中部开始形成空腔, 为初始的消化道腔。2 日龄仔鱼全长2.61～2...  相似文献   

肝癌与地形地貌类型关系初探     

曾昭华  曾雪萍 《南方国土资源》1997,(2)

文章利用地形地貌资料４５０２个数据，肝癌死亡调查资料８３４３例，研究了肝癌死亡率与人群生存的地形地貌类型的相关性。在此基础上综合评价了与肝癌有相关性的地形地貌类型对肝癌产生和发展的影响  相似文献   

Racial/ethnic,area socioeconomic,and geographic disparities of cervical cancer survival in Texas     

《Applied geography (Sevenoaks, England)》2015

A better understanding about the factors associated with cervical cancer survival disparities is an important step in developing more effective cervical cancer intervention strategies. This study investigates cervical cancer survival disparities from three different perspectives based on data from the Texas Cancer Registry from 1995 to 2005. These perspectives are race/ethnicity, area socioeconomic status (SES), and geographic locations. We examined the role of both individual- and contextual-level factors in cervical cancer survival disparities using a multilevel survival analysis. Individual-level factors included race/ethnicity, age at diagnosis, year of diagnosis, tumor grade, stage at diagnosis, and type of treatment received. Contextual-level factors are census-tract-level variables, including demographic characteristics, health insurance expenditure, behavioral factors, extent of urbanization, and spatial access to primary care physicians. This study reveals that African-Americans had a higher mortality risk (HR, 1.19; 95% CI, 1.03–1.38) especially if stage was unknown (HR, 1.72; 95% CI, 1.08–2.75) compared with non-Hispanic whites. Among women diagnosed at regional or distant stage, Hispanics had a survival advantage over their non-Hispanic white counterparts (HR, 0.80; 95% CI, 0.69–0.94). We also identified geographic areas where longer-than-expected or shorter-than-expected cervical cancer survival was statistically significant. Only a small portion of these disparities were explained by individual- and contextual-level factors. This study suggests that Race/Ethnicity, SES, and geography are associated with cervical cancer survival in Texas.  相似文献   

云南宣威晚二叠世末生物灭绝期C1煤的地球化学特征     

邵龙义  王娟  侯海海  张名泉  汪浩  SPIRO Baruch  LARGE Davi  周义平 《地质学报》2015,89(1):163-179

云南宣威雁塘煤矿晚二叠世末期C1煤层蕴含了二叠纪—三叠纪界线事件演化以及宣威肺癌高发原因方面的重要信息。本文对该矿C1煤层(包括三个分层——B1、B2和B3)进行了刻槽分层采样,采用X射线荧光光谱和电感耦合等离子体质谱测试了24个样品中常量和微量元素。利用偏光显微镜和带能谱的扫描电镜(SEMEDX)对煤中的显微组分及矿物组成进行微区分析,利用X射线衍射对低温灰化后的煤样作了矿物的半定量分析。结果表明,雁塘矿C1煤中常量元素Ca、Mn、Si含量明显高于中国煤均值;与华南二叠纪煤平均值、中国煤平均值、世界煤平均值以及地壳元素丰度相比较,雁塘矿C1煤中的W、Co、Mo、Cd、Pb、Be、Sb、Cu、Ni、Zn、Zr和V等12种微量元素相对比较富集。结合相关分析和SEM-EDX微区分析方法,对C1煤中微量元素的赋存状态进行分析发现Cs、Ga、Nb、Ba、Rb、Th、Tl、U与灰分显著正相关,表明这些元素主要以无机矿物态赋存,其它元素赋存状态复杂。结合C1煤中12种富集元素在垂向上的含量分布特征,推断Co、Cu、V、Zn应主要来源于峨眉山玄武岩风化产物;Be和Zr主要受同沉积火山灰影响;Ni则可能受峨眉山玄武岩风化及同沉积火山灰的共同影响;同沉积火山灰是C1煤中W来源之一;Sb可能受中低温热液的影响。C1煤中Zr与我国南方其他地区P/T界线粘土岩中Zr的富集规律一致。C1煤中富集的微量元素与宣威肺癌高发区可吸入颗粒物中的高含量元素一致,推断C1煤的燃烧可能与宣威肺癌高发有关。C1煤中富集的有毒有害微量元素可能与二叠纪—三叠纪之交生物大灭绝期的独特环境有密切关系。  相似文献   

河南省肺癌空间分布格局及环境因素影响   总被引：2，自引：0，他引：2  

魏海涛  刘岩  田智慧  王晓蕾  赫晓慧  韦晶 《地理学报》2022,77(1):245-258

肺癌是最常见的恶性肿瘤之一,也是主要的肿瘤死因,河南省肺癌发病率和死亡率常年居恶性肿瘤首位,研究肺癌的空间分布格局及其与环境因子的关系对肺癌的相关防控工作意义重大。本文以2016—2018年河南省肺癌发病数据为研究对象,使用空间自相关分析方法研究河南省肺癌的空间分布格局,基于地理探测器量化各个环境因子及其两两交互作用对肺癌发病率的解释力。结果表明：空间上肺癌具有明显的集聚特征,高发区集中分布于豫中、豫东和豫南的平原和盆地地区。在所选的12种环境因子中,PM_2.5浓度、O₃浓度、年均风速、采矿业从业人员占比、人均GDP具有更高的决定力,人均GDP和医护人员占比则对多种要素的决定力均具有明显的非线性增强的作用。研究结果可以为河南省肺癌发病机理研究和相关防治工作提供科学支撑。  相似文献   

Late-Stage Breast Cancer Diagnosis and Health Care Access in Illinois∗     

Fahui Wang  Sara McLafferty  Veronica Escamilla  Lan Luo 《The Professional geographer》2013,65(1):54-69

The variations of breast cancer mortality rates from place to place reflect both underlying differences in breast cancer prevalence and differences in diagnosis and treatment that affect the risk of death. This article examines the role of access to health care in explaining the variation of late-stage diagnosis of breast cancer. We use cancer registry data for the state of Illinois by zip code to investigate spatial variation in late diagnosis. Geographic information systems and spatial analysis methods are used to create detailed measures of spatial access to health care such as convenience of visiting primary care physicians and travel time from the nearest mammography facility. The effects of spatial access, in combination with the influences of socioeconomic factors, on late-stage breast cancer diagnosis are assessed using statistical methods. The results suggest that for breast cancer, poor geographical access to primary health care significantly increases the risk of late diagnosis for persons living outside the city of Chicago. Disadvantaged population groups including those with low income and racial and ethnic minorities tend to experience high rates of late diagnosis. In Illinois, poor spatial access to primary health care is more strongly associated with late diagnosis than is spatial access to mammography. This suggests the importance of primary care physicians as gatekeepers in early breast cancer detection.  相似文献   

表现局灶性磨玻璃密度肺癌的CT诊断与随访分析          下载免费PDF全文

包亚红  成钢 《CT理论与应用研究》2016,25(2):219-225

目的:分析局灶性磨玻璃密度(f GGO)肺癌的CT表现,以提高诊断早期肺癌的准确率。方法:搜集经手术病理证实的、临床及CT资料完整的、表现为磨玻璃密度的肺癌病例34例,作回顾性分析,观察病灶大小、形态、边缘、密度及其他肺癌倾向征象,以及病灶在随访过程中的影像学变化。结果:34例患者中p GGO 7例,m GGO 27例,瘤肺界面清晰,病灶边缘可见分叶、毛刺,病灶内部可见空泡、支气管充气征,病灶周围可见胸膜凹陷征、血管集束征等。f GGO在随访过程中,病灶增大,密度增高,p GGO病灶内部出现实性成分,m GGO病灶内实性成分增多,病灶边缘出现分叶、毛刺,周围出现胸膜凹陷征、血管集束征等恶性征象。结论:f GGO肺癌的CT表现具有一定的特征性,CT随访对f GGO的良恶性鉴别具有较高的价值。   相似文献