2005年成都市麻疹模拟实时监测与预警研究

目的探索前瞻性时空重排扫描统计量在麻疹早期预警中的应用。方法模拟实时监测,采用前瞻性时空重排扫描统计量,对成都市2005年麻疹数据进行逐日前瞻性分析。结果以6月份预警结果为例,6月10日发出预警信号,该预警信号包括的天数为2 d,所包括的乡镇街道为武侯区的簇桥街道和金花桥街道。结论前瞻性时空重排扫描统计量能充分利用数据信息,及时探测到传染病的聚集性发病。     

前瞻性时空扫描统计量在传染病早期预警中的应用

目的 探索前瞻性时空扫描统计量在传染病早期预警中的应用.方法 模拟实时监测系统,采用前瞻性时空扫描统计量对2005年成都市102个乡镇街道的3212例细菌性痢疾病例数据进行逐日前瞻性分析,并与单纯时间聚集性分析结果相比较.结果 前瞻性时空扫描统计量可提供确切的预警信息,对细菌性痢疾进行时间和空间定位.从6月的预警结果可见,前瞻性时空扫描统计量及时探测到了细菌性痢疾的局部暴发,且预警信号较强(P=0.007).而单纯时间聚集性分析滞后2 d发出预警,且信号较弱(P=0.039).结论 前瞻性时空扫描统计量能够充分挖掘和利用传染病监测数据中的时间和空间信息,能够提高聚集性探测的及时性和有效性,在实际工作中具有潜在的重要应用价值.     

前瞻性时空扫描统计量方法在手足口病暴发预警中的参数筛选

目的 根据手足口病的流行特点,比较和筛选时空扫描统计量方法较好的预警参数,从而更好的应用于手足口病暴发早期探测预警.方法 以真实的暴发事件作为参考数据,灵敏度、探测时间间隔和阳性预测值为评价指标,采用前瞻性时空扫描统计量方法,利用不同时空参数对山东省青岛市2009年6月手足口病病例数据逐日模拟预警探测,比较4种参数不同设定值的24种预警效果.结果 时间窗口设置为3天和基线设置为最近21天的病例数据进行时空扫描统计量预警运算,具有最优的预警效果.候选聚集区域范围的设定对预警效果无统计显著性.结论 采用前瞻性时空扫描统计量进行传染病暴发预警时,具有最优的参数,但相同的传染病在不同区域可能有不同的预警参数,下一步应该根据相同传染病在不同地区筛选最优参数方案.     

基于前瞻性时空重排扫描统计量的传染病早期预警系统

目的探索前瞻性时空重排扫描统计量在传染病早期预警中的应用。方法模拟实时监测系统,采用前瞻性时空重排扫描统计量对成都市2005年麻疹病例数据进行逐日前瞻性分析。结果前瞻性时空重排扫描统计量能早期探测到传染病的爆发。结论利用前瞻性时空重排扫描统计量结合地理信息软件建立的早期预警系统,能有效地对传染病爆发做出早期预警。     

基于超几何分布的前瞻性时空扫描统计量在疟疾早期预警中的应用北大核心CSCD

目的探索基于超几何分布概率模型的前瞻性时空扫描统计量在疟疾早期预警中的应用。方法利用R语言编程实现两种前瞻性时空扫描统计量,分别基于经典的泊松分布概率模型和较新的超几何分布概率模型,模拟实时监测系统对四川省2009年疟疾病例中6月21日-30日连续10天数据进行逐日前瞻性分析。结果基于超几何分布的前瞻性时空扫描统计量和基于泊松分布的前瞻性时空扫描统计量在疟疾早期预警中效果相当,都能早期探测到疟疾的爆发。结论基于超几何分布的前瞻性时空扫描统计量在疟疾早期预警中有应用价值。     

基于超几何分布的前瞻性时空扫描统计量在疟疾早期预警中的应用

目的探索基于超几何分布概率模型的前瞻性时空扫描统计量在疟疾早期预警中的应用。方法利用R语言编程实现两种前瞻性时空扫描统计量,分别基于经典的泊松分布概率模型和较新的超几何分布概率模型,模拟实时监测系统对四川省2009年疟疾病例中6月21日-30日连续10天数据进行逐日前瞻性分析。结果基于超几何分布的前瞻性时空扫描统计量和基于泊松分布的前瞻性时空扫描统计量在疟疾早期预警中效果相当,都能早期探测到疟疾的爆发。结论基于超几何分布的前瞻性时空扫描统计量在疟疾早期预警中有应用价值。     

基于网络直报系统和时空聚集性探测的传染病模拟实时监测与预警

[目的]基于网络直报系统数据,模拟实时监测,探索前瞻性时空扫描统计量在传染病早期预警中的应用.[方法]模拟实时监测系统,采用前瞻性时空扫描统计量对上海市、江苏省、浙江省214个区县2005年1月1日到12月31日麻疹病例数据进行逐日前瞻性时空聚集性分析.[结果]前瞻性时空扫描统计量能有效探测到麻疹时空聚集性.其中开始于3省交界区县的麻疹时空聚集性有较强的实际意义.[结论]前瞻性时空扫描统计量能充分挖掘和利用传染病监测数据信息,探测到时空两个维度的聚集性,在实际工作中具有潜在的重要应用价值.     

前瞻性时空扫描统计量与时空重排扫描统计量在传染病聚集性探测中的适用性探讨

目的探讨前瞻性时空扫描统计量与时空重排扫描统计量在传染病聚集性探测中的适用性。方法以成都市2009年5、6月细菌性痢疾病例数据为例,分别采用前瞻性时空扫描统计量与时空重排扫描统计量,运用SaTScan9.0软件进行聚集性探测,并对结果进行比较分析。结果前瞻性时空扫描统计量扫描结果与成都各区县实际发病轨迹较接近,前瞻性时空重排扫描统计量在发病率较低的区域扫描结果有相对较多的误报。结论由于前瞻性时空扫描统计量考虑了人口数据信息,在低发病区域,实际应用中应尽量采用时空扫描统计量进行聚集性探测。     

扫描统计量在麻疹聚集性分析中的应用探讨

目的 探讨扫描统计量在麻疹实时预警和时空聚集性分析中的应用价值。方法 应用前瞻性时空扫描统计量结合空间准确性评价指标MCS-P(Most Clustering Set-Proportion)去确定最优参数,对北京市朝阳区2016年网络直报的麻疹数据开展模拟预警分析。同时应用空间扫描统计量结合MCS-P分析2006-2016年北京市朝阳区麻疹聚集性。结果 模拟预警提示3月4日双井街道麻疹病例出现异常聚集,与历史监测资料一致。麻疹发病数从2006年后直线下降,但在2009年后出现反复。 2014-2016年,麻疹的局部高发区域的形状较为规则,波及范围更大但并未带来更高的空间聚集性。2014-2016连续三年,十八里店乡、高碑店乡以及豆各庄乡均表现出空间聚集性。结论 运用前瞻性时空扫描统计量结合MCS-P选用最优参数进行逐日分析,可以得到最符合实际情况的聚集区域,在早期预警中具有实际价值。分析连续多年数据有助于发现麻疹分布模式的变化以及空间分布特征,从而发现高危地区,以便进一步分析原因并采取针对性地干预措施。     

扫描统计量在传染病监测应用中的空间尺度选择

[目的]探讨如何选择时空扫描统计量在传染病监测应用中适宜的最小空间尺度。[方法]分别以地市和区县作为最小空间尺度运用时空扫描统计量对2007～2009年河南省麻疹数据进行模拟监测和分析。[结果]以地市为最小空间尺度时产生5个信号,并均能在以区县为最小空间尺度产生的9个信号找到对应信号。[结论]本文以实例分析初步探讨了时空扫描统计量对最小空间尺度的选择,就麻疹而言,以区县为空间尺度进行聚集性探测较为合理。     

南京市男男性行为人群随访中队列保持研究

目的 了解南京市男男性行为人群(men who have sex with men,MSM)随访中HIV新发感染率、队列保持情况及其影响因素.方法 采用前瞻性队列研究,于2008年4月始对符合纳入标准的361名MSM招募者进行间隔6个月和12个月的随访,检测HIV抗体,估算HIV抗体阳转率,并分析MSM的社会人口学和高危行为特征与12个月时队列保持率的关系.结果 南京MSM队列12个月的HIV抗体阳转率为5.09/100人年,随访12个月时队列保持率为61.5%.多因素Logistic回归分析显示,与队列保持率有统计学意义的变量为户籍所在地为南京(OR=2.430,95% CI=1.409～4.190)、6个月能随访到(OR=11.664,95% CI=6.509～20.901)、寻找性伴场所为互联网(OR=2.222,95% CI=1.228～4.022)、近1年参加同伴教育活动(OR=2.080,95% CI=1.095～3.950)和年龄大于30岁(OR=3.296,95% CI=1.737～6.253).结论 该地区MSM人群中有较高的HIV新发感染率和高危性行为暴露率,户籍为当地、年龄较大、近1年接受过同伴教育以及通过互联网寻找性伴的MSM较容易保持在随访队列中.     

Use of a prospective space-time scan statistic to prioritize shigellosis case investigations in an urban jurisdiction

OBJECTIVE: A prospective space-time scan statistic was applied to Chicago's 2002 shigellosis surveillance data to evaluate its utility in objectively describing clusters and assisting in the prioritization of investigations. METHODS: The prospective space-time module of SaTScan, a free software available online, was used to identify "live" clusters of disease, meaning cases that were current as of the date of the analysis and strongly associated in place and time. Fifty-two separate space-time analyses were run; one simulation for each week of 2002. Identified clusters were described in terms of space, time, risk factors reported by involved case-patients, and cases' links to venue-associated outbreaks. RESULTS: Twelve live clusters were detected at the p < 0.05 significance level: two single-household clusters and 10 community clusters. The community clusters ranged in size from 194 to 367 census tracts (median = 294), and in disease burden from 21 to 41 cases (median = 29). Geographically, all of the community clusters were located in the west-central part of the city and had a temporal span of 28 days. Within the 10 community clusters, 15 different day care centers were identified as potential exposure settings for case-patients or their close contacts. CONCLUSIONS: The prospective space-time scan statistic offers local health departments an objective way of describing clusters of shigellosis cases. The method used in this study could help prioritize the assignment and investigation of cases, particularly when overall shigellosis incidence exceeds expected numbers or when an agency's resources are stressed by other events, such as outbreaks.     

Height, leg length, and cancer: the Caerphilly Study

The incidence of several cancers increases with height. Some studies report that leg length, a marker of prepubertal growth, is the component of height underlying these associations, but few prospective studies have investigated this issue. We examined height-cancer associations in a 21-yr follow-up of a cohort based on 2,512 men aged 45-59 living in the town of Caerphilly, South Wales, U.K., between 1979 and 1983. The men underwent a detailed examination, and 2,393 (95.3%) had measures of height and sitting height (from which leg length and trunk length were derived) recorded and were cancer-free at baseline. Cox proportional hazards models were used to investigate associations of height, leg length, and trunk length with overall and site-specific cancer incidence; 328 men developed cancer over the follow-up period. Associations with height were weak and did not reach conventional levels of statistical significance. In models controlling for age, socioeconomic position, smoking, and body mass index, cancer incidence was weakly positively associated with increases in height; hazard ratio (HR, 95% confidence interval) per standard deviation (6 cm) increase in height was 1.09 (0.97, 1.21; P = 0.14). Associations were somewhat stronger in relation to leg length (HR 1.09; (0.97-1.22) than trunk length (HR 1.05; 0.94-1.18). Height-cancer associations were strongest for lung cancer (HR 1.21; 0.96-1.51). This analysis provides limited support for the suggestion that leg length is the component of height underlying height-cancer associations     

Baseline self-perceived risk of HIV infection independently predicts the rate of HIV seroconversion in a prospective cohort of injection drug users

BACKGROUND: The identification of individuals at the highest risk of human immunodeficiency virus (HIV) infection is critical for targeting prevention strategies. We evaluated self-perceived risk of HIV infection and rates of subsequent HIV seroconversion among a prospective cohort study of injection drug users (IDUs). METHODS: We performed an analysis of the time to HIV infection among 994 baseline HIV negative IDUs enrolled in the Vancouver injection drug users study (VIDUS). IDUs were stratified based on their baseline self-perceived risk of HIV seroconversion (higher than others vs same or lower). Kaplan-Meier methods were used to estimate cumulative HIV incidence rates and Cox regression was used to determine adjusted relative hazards for HIV seroconversion. RESULTS: At the end of 24 months after enrolment into the cohort, the cumulative HIV incidence rate was significantly elevated among the 5.9% of the sample who perceived their risk for HIV infection to be higher at baseline (26.6% vs 7.8% log-rank P < 0.001). In a Cox model that adjusted for all variables that were associated with the time to HIV infection in univariate analyses, a higher baseline self-perceived risk of acquiring HIV infection (relative hazard RH: 2.48 [95% Confidence interval (CI): 1.51, 4.10]; P = 0.004) remained independently associated with time to HIV seroconversion. CONCLUSIONS: IDUs' perception of their risk for HIV seroconversion upon enrolment into a prospective cohort study was strongly and independently associated with the subsequent rate of HIV seroconversion. Since this risk marker remained independently associated with HIV seroconversion, even after adjustment for time-updated risk behaviours, our findings have major implications that may aid outreach workers in their efforts to identify IDUs who should be targeted with prevention efforts.     

Shift work and the risk of diabetes mellitus among Japanese male factory workers

OBJECTIVES: This study investigated whether shift work is a risk factor for the development of diabetes mellitus. METHODS: The workers, 2860 men in a sash and zipper factory in the Toyama prefecture of Japan, were followed for 8 years, and the incidence rate of diabetes mellitus was determined. The cohort contained fixed daytime blue-collar workers, shift blue-collar workers, and white-collar workers. The workers were considered to have diabetes mellitus if, in their annual health examination, they had a glycated hemoglobin level of > or = 6.1 or if the diagnosis had been made by a hospital physician. The relative risks were estimated by Cox's proportional hazards regression model. RESULTS: Among the 2860 workers, there were 87 cases of new-onset diabetes mellitus, resulting in an incidence rate of 4.41 per 1000 person-years. The age-adjusted incidence was highest for the two-shift workers and lowest for the white-collar workers. The relative risk of diabetes mellitus for the two-shift workers and the three-shift workers compared with the fixed daytime workers was 1.73 and 1.33, respectively, after adjustment for all the confounding factors, but these values were not statistically significant. When the white-collar workers were used as a reference group, a significantly increased risk of diabetes mellitus was found for the two-shift workers (relative risk was 2.01 after adjustment for all confounding factors), but not for the three-shift workers or the fixed daytime blue-collar workers. CONCLUSIONS: The study suggests that shift work is a risk factor for the onset of diabetes mellitus and that there is a different risk associated with different shift schedules.     

河南省扩大免疫规划阶段流行性腮腺炎流行特征和时空聚集性

  目的  分析河南省2008-2019年流行性腮腺炎的时空分布特征，识别高危聚集区，为流行性腮腺炎的防控提供科学建议。  方法  基于中国传染病监测信息报告管理系统，通过描述性流行病学方法分析河南省2008-2019年流行性腮腺炎三间分布特征。采用ArcGIS 10.7软件进行三维趋势分析和结果可视化呈现，应用SaTScan 9.4软件进行时空扫描分析。  结果  河南省2008-2019年累计报告223 499例流行性腮腺炎，年平均报告发病率为19.68/10万；病例主要集中在5~10岁儿童和青少年，占病例总数的50.61%；每年的3-7月及11月-次年1月为发病高峰。三维趋势分析显示，河南省流行性腮腺炎发病由南向北逐渐升高，且东部略高于西部；时空扫描统计结果显示:共识别到6个时空聚集区，主要聚集区位于北部安阳地区，包含4个县区，聚集时间为2008-2013年。  结论  2008-2019年河南省流行性腮腺炎发病水平呈平稳的波动趋势，且存在明显季节性规律，5~10岁的儿童和青少年为其主要发病人群，2008-2019年河南省流行性腮腺炎存在时空聚集性，主要聚集区呈动态变化，近两年东南部地区出现聚集区，应重点关注。     

Temporal surveillance using scan statistics

We describe two classes of statistics for testing an arbitrary model of disease incidence over time against an alternative model involving a spike (pulse) superimposed on this background. The statistics are each based on taking the maximum of some function comparing observed and expected numbers of events in a window of width w. One approach applies p-values for scan statistics calculated for a constant background rate to this more general problem. For a fixed window, w, the approach gives a simple formula to determine p-values for retrospective analysis, or to sound an alarm for either continuous or grouped prospective data. The latter application involves a new approximation for the distribution of the maximum number of cases in w consecutive intervals. The second approach based on generalized likelihood ratio tests (GLRTs), sounds an alarm for a higher than anticipated rate of events in a scanning window of fixed length, or for window sizes that lie in a region. GLRTs are constructed for continuous observations, for grouped data, or for a sequence of trials. As for GLRTs used in retrospective evaluations, simulation is required to implement the prospective procedure.For grouped surveillance data, we compare by simulation, operating characteristics of the P-scan with fixed windows (both correctly specified and not), the fixed-window GLRT, the variable-window GLRT, and a variant of the CUSUM. The simulations demonstrate a very high correlation between the P-scan and corresponding fixed-window GLRT.     

Epidemiologic methods for prospective assessment of menstrual cycle and reproductive characteristics in female semiconductor workers

Methods were developed to assess potential adverse effects of semiconductor fabrication work in a prospective study of reproductive health. All women aged 18–44 years who worked in seven silicon-wafer fabrication sites in five companies and a frequency-MAtched sample of women in nonfabrication jobs were included. Among 3,480 selected for screening, 2,639 (75%) completed a self-administered questionnaire to identify women at risk of pregnancy. Among the 739 (28%) eligible women, 481 (65%) completed baseline interviews and 402 (83.6%) completed at least one menstrual cycle of follow-up by providing daily diaries and daily urine samples. Menstrual cycle characteristics were assessed from questionnaires and diaries. Urine samples were assayed for reproductive hormones to identify conceptions. The usual cycle length recalled at baseline was 28 days. The mean cycle length (MCL) recorded in diaries was 29 days, with greater dispersion than at baseline. The median of the MCL from diary data was 28 days for women reporting regular cycles at baseline but 34 days for women reporting irregular cycles at baseline, and the median standard deviation in cycle length per woman was 2.5 days and 7.5 days, respectively. The prospective method, while expensive and labor intensive, showed good compliance. Nevertheless, recall also provided reasonably accurate Estimates and distinguished women with regular and irregular cycles.     

应用SaTScan与FleXScan识别丙型肝炎发病的高风险区域

目的 探测2015年上海市浦东新区丙型肝炎（简称"丙肝"）发病的空间聚集性,识别丙肝发病的高风险区域;比较SaTScan与FleXScan在疾病空间聚集性探测方面的应用效果。方法 收集2015年浦东新区丙肝的发病数据,以街道和镇为分析单位,分别采用SaTScan 9.4.4与FleXScan 3中的Poisson模型探测丙肝发病空间聚集区域;并通过调整参数比较两个软件在不同参数设置下所探测到的聚集区域的位置和范围的变化情况。结果 上海浦东2015年丙肝发病率为12.72/10万;SaTScan和FleXScan均只扫描到一个具有统计学意义（P<0.05）的空间聚集区域,分别包含10个镇（川沙新镇、大团、合庆、惠南、祝桥、宣桥、周浦、新场、老港和万祥）和4个镇（川沙新镇、张江、曹路和合庆）,两种方法的扫描结果均覆盖了川沙新镇和合庆镇;SaTScan的窗口比例从50%变化到25%,聚集区域范围减少了一个镇,FleXScan设定不同K值所探测到的聚集区域变化范围较大。结论 上海浦东新区2015年丙肝发病存在空间聚集性,结合SaTScan的和FleXScan的扫描结果认为川沙新镇和合庆镇是浦东丙肝发病的高风险区域和重点防控区域。     

Home dampness and molds, parental atopy, and asthma in childhood: a six-year population-based cohort study

Previous studies of how parental atopy and exposure to dampness and molds contribute to the risk of asthma have been mainly cross-sectional or prevalent case-control studies, where selection and information bias and temporality constitute problems. We assessed longitudinally the independent and joint effects of parental atopy and exposure to molds in dwellings on the development of asthma in childhood. We conducted a population-based, 6-year prospective cohort study of 1,984 children 1-7 years of age at the baseline in 1991 (follow-up rate, 77%). The study population included 1,916 children without asthma at baseline and complete outcome information. The data collection included a baseline and follow-up survey. The outcome of interest was development of asthma during the study period. The studied determinants were parental allergic diseases and four indicators of exposure at baseline: histories of water damage, presence of moisture and visible molds, and perceived mold odor in the home. A total of 138 (7.2%) children developed asthma during the study period, resulting in an incidence rate of 125 cases per 10,000 person-years [95% confidence interval (CI), 104-146]. In Poisson regression adjusting for confounding, parental atopy [adjusted incidence rate ratio (IRR) 1.52; 95% CI, 1.08-2.13] and the presence of mold odor in the home reported at baseline (adjusted IRR 2.44; 95% CI, 1.07-5.60) were independent determinants of asthma incidence, but no apparent interaction was observed. The results of this cohort study with assessment of exposure before the onset of asthma strengthen the evidence on the independent effects of parental atopy and exposure to molds on the development of asthma.