湖沼型血吸虫病流行区钉螺抽样方法的对比研究

目的优化、简化湖沼型血吸虫病流行区钉螺调查方法,提高钉螺调查精度、效率和经济性。方法基于鄱阳 湖区域恒湖农场茶叶港草洲1块50 m×50 m试验样地,全覆盖查螺后再分别采用简单随机抽样、系统抽样与分层抽样等3 种方法进行钉螺调查,计算最小需求样本量、抽样相对误差与抽样绝对误差。结果本研究中简单随机抽样、系统抽样 与空间分层抽样等3种方法的最小需求样本量分别为300、300和225,抽样相对误差均小于15%,抽样绝对误差分别为 0.221 7,0.302 4和0.047 8。结论用高程作为分层依据进行空间分层抽样是钉螺实际调查中节省成本、提高精度的有 效途径。     

首次全国人体寄生虫分布调查抽样设计和效果评价

全国人体寄生虫分布调查（１９８８～１９９２）是几十种寄生虫的同时调查，影响的因素多而复杂，因此抽样设计有一定难度，本文从３个方面进行了设计，并考虑到自然因素和社会因素对寄生虫分布及感染率的影响，采取了分层整群随机抽样方法。抽样设计的核心是要尽量减少抽样误差，本文从分析计算抽样误差有关公式入手，设计了３个减少抽样误差的措施。调查最后结果证实，这次的抽样设计对误差的控制取得了良好的效果。     

抽样调查中居民血吸虫感染率误差分析方法的探讨

目的 :建立日本血吸虫病抽样调查居民感染率的误差分析和统计方法。方法 :按照多重分层、整群随机抽样的要求 ,应用误差传递理论 ,结合整群随机抽样和分层随机抽样标准误的计算公式 ,对居民血吸虫感染率抽样误差进行统计分析和理论推导。结果 :得出流行省份及其不同类型未控制流行地区居民血吸虫感染率的抽样误差的 4个公式。结论 :推导并建立多重分层、整群随机抽样误差的计算公式。     

首次全国人体寄生虫分布调查抽样设计和效果评价

全国人体寄生虫分布调查是几十种寄生虫的同时调查，影响的因素多而复杂，因此抽样设计有一定难度，本文从３个方面进行了设计，并考虑到自然因素和社会因素对寄生虫分布及感染率的影响，采取了分层整群随机抽样方法，抽样设计的核心是要尽量减少抽样误差，本文从分析计算抽样误差有关公式入手，设计了３个减少抽样误差的措施，调查最后结果证实，这次的抽样设计对误差的控制取得了良好的效果。     

寄生虫感染与预防知识的关系

对上海郊区１０个县１２个整群抽样点的５４７９人进行了寄生虫病预防知识和粪便检查的调查。结果表明居民的预防知识平均为４１．８６分（满分为１１０分）；男性的分数显著地高于女性（ｔ＝５．２５，Ｐ＜０．０１），平均分数随着文化程度的升高而上升；不同年龄分组中，又以１５岁组的分数最高。粪便检查结果表明，总感染率为５２．２％；男女性别间无显著性差异；感染率随文化程度的增高而下降；５岁年龄组感染率最高。寄生虫虫种以蛔虫、鞭虫和蛲虫为主，各抽样点的常见寄生虫感染率及总感染率经反正弦函数转换后与平均分数的分析结果表明，蛔虫蛲虫感染率均与平均分数有相关关系；列出了相应的回归方程式。     

全国血吸虫病抽样调查样本量估算方法的探讨

根据分层整群抽样方法中居民血吸虫感染率的标准误和误差范围的要求，应用统计学原理，为全国血吸虫病抽样调查各省未控制流行地区建立样本量（样本村村数和应检人数）的估算方法。     

全国血吸虫病抽样调查抽样方法及抽样误差

１９９５年全国血吸虫病抽样调查，采取分层整群随机抽样方法［１］进行抽样，根据调查资料推算居民血吸虫感染率及其抽样误差，是一项必要的工作。居民感染率是反映血吸虫病流行程度的重要指标，抽样误差是反映抽样方法是否达到了设计要求的评价指标。现应用统计学有关概念，对抽样方法以及全国、各省未控制流行地区抽样误差，分别加以探讨。１抽样方法 分层整群随机抽样方法，以省为主层，以行政村为单位的血吸虫病流行村为抽样单元，所有的流行村构成抽样总体。先分层再抽样，具体内容和做法见图１所示。１．１未控制地区按流行区类型及…     

消除碘缺乏病考核验收抽样方法及参数估计

２０００年全球实现消除ＩＤＤ目标，如何评价各省是否“达标”？除依据其标准外，必须科学地制定实施标准的具体方法，作者提出消除ＩＤＤ“三级二层整群”考核验收抽样方法，是集单纯随机抽样、分层抽样，整群抽样”四位一体”综合抽样方法，既达到样本例数要求，又具有代表性，既可控制或减少系统误差及抽样误差，又能节省大量人力，物力，才力和时间，是一种科学合理实用的抽样方法。     

乌鲁木齐南郊农牧区囊型包虫病流行病学研究

目的了解乌鲁木齐南郊农牧区囊型包虫病流行现状及其流行病学特征。方法采取定点整群抽样的方法，对居民进行体检和血清学检测，确定居民囊型包虫病的感染率和患病率;用粪抗原检测法调查家犬细粒棘球绦虫感染率，通过问卷调查方法了解居民养犬情况。结果乌鲁木齐南郊农牧区居民囊型包虫平均感染率为35.7%（687/1925），平均患病率为1.12%（23/2049）。高山牧场居民包虫感染率最高，半农半牧地区次之，单纯农业区最低。包虫病患病率以农牧结合区最高，单纯农业区次之，高山牧场最低。结论乌鲁木齐南郊牧区囊型包虫病的传播呈现高度活跃状态，居民包虫感染率和患病率与民族、性别、年龄及养犬等有关。     

2014—2015年全国人体重点寄生虫病现状调查的抽样设计及解读

我国于2014-2015年开展了全国人体重点寄生虫病现状调查本次调查覆盖31个省(自治区、直辖市),采用多阶段随机整群抽样。调查分为农村和城镇两部分,农村地区抽样依据土源性线虫病流行水平,分层因素包括省份、生态区和经济因素。城镇地区抽样依据华支睾吸虫病流行水平,将全国分为5类,其中4个重点流行省份根据各自流行水平进行分层抽样:本次调查抽样设计充分考虑病种和人群特征差异,以最大实现样本的代表性。     

血吸虫病抽样调查居民感染率及感染者例数推算方法的探讨

目的：探讨血吸虫病抽样调查居民感染率及感染者例数的推算方法。方法：结合多重分层整群随机抽样方法的特点，应用血吸虫病流行病学和医学统计学原理，对居民感染率及感染者例数的统计方法进行理论推导。结果：得出各流行省及其不同类型未控制流行区的居民感染率及感染者例数的１套理论计算公式。结论：推算方法简明、合理，有实际应用价值。     

辽宁省第四次结核病流行病学抽样调查报告

目的　评价1991-2000年全省结核病防治规划和世行贷款辽宁结核病控制项目实施效果,掌握结核病流行状况。方法 本次流调方法与全国第四次流调方法基本一致,采用分层整群等比例随机抽样方法。结果 全省活动性、涂阳、菌阳肺结核患病率和结核病死亡率分别为130.8/10万、56.3/10万、66.3/10万和2.9/10万。结论 全省活动性肺结核患病率和死亡率下降显著,涂阳和菌阳患病率呈下降趋势,但下降速度缓慢。     

青海省学生包虫病防治知识现状调查

目的了解青海省学生包虫病防治知识掌握状况,为包虫病防治工作提供科学依据。方法采用多阶段分层 整群抽样方法,抽取青海省4年级及以上学生进行包虫病相关知识问卷调查。结果共抽取并调查青海省4年级及以 上学生23 600名,问卷调查总合格率为66.0%（15 566例）,其中男生合格率为65.1%（7 947例）,女生合格率为66.9% （7 619例）,差异有统计学意义（ χ2 = 8.454,P < 0.01）。不同地区问卷调查合格率存在统计学差异（ χ2 = 3 848.619,P < 0.01）。结论青海省学生的包虫病防治知识掌握情况总体不高,应加强健康教育,并侧重对牧区学生的干预。     

Critical Issues and Further Questions About Respondent-Driven Sampling: Comment on Ramirez-Valles, <Emphasis Type="Italic">et al</Emphasis>. (2005)

The application of respondent-driven sampling (RDS) is a promising new approach to understanding hidden populations, including those at high risk for HIV infection. The method has significant advantages over other sampling methods, including the possibility that representativeness samples can be accrued. However, the requirements for a respondent-driven sample to achieve representative and to demonstrate its superiority over other methods are quite strict. This report focuses on whether the accompanying paper by Ramirez-Valles et al. fulfills these requirements in terms of the theorems underlying RDS regarding sample recruitment rates, referral patterns, and network sizes. Further, it investigates the assertion that the accrued sample has proven that RDS is superior to more traditional time-location or venue-based sampling methods. Unconvinced that either is the case, the author suggests a method to test if RDS is indeed the gold-standard recruitment strategy for obtaining inclusive and representative samples of hidden populations.     

Endoscopic ultrasound-guided tissue acquisition of lymph nodes

One of the most common indications for endoscopic ultrasound (EUS)-guided tissue sampling is to diagnose the etiology of suspicious lymphadenopathy. Although most cases of lymphadenopathy are benign and self-limiting, patients with deep-seated lymph nodes living in tuberculosis endemic areas or with suspected malignancy require tissue diagnosis to guide treatment. Fine-needle aspirate and fine-needle biopsy systems have excellent reliability for evaluating both benign and malignant lymph node diseases. The advent of new technologies and addition of ancillary molecular diagnostics have improved the diagnostic potential obtained by fine-needle sampling. In turn, the clinical applications of EUS tissue sampling have evolved and further expanded to include granulomatous diseases and lymphoma. Optimizing tissue acquisition to obtain high-quality specimens is of utmost importance and may be achieved with operative strategies unique to lymph node sampling. This chapter discusses the powerful clinical impact of EUS-guided lymph node sampling and technical considerations of optimizing diagnostic yield.     

江苏省慢性丝虫病现状调查

目的 了解江苏省慢性丝虫病患病现状，为开展丝虫病防治和慢性丝虫病治疗提供依据。方法 采用分层整群抽样和线索调查2种方法，对全省71个原丝虫病流行县15周岁以上人群进行慢性丝虫病症状、体征和实验室检查，对调查资料进行统计分析。结果 抽样调查慢性丝虫病患病率为0．15％，推算全省有慢性丝虫病病人65298例。线索调查发现病人9793例。年龄17～92岁，60岁以上者占65．39％，病程1～64年，10年以上者占91．09％，临床分型以下肢淋巴液肿居多，占69．35％。34个丝虫病中度流行县的推算病例数占全省病例数的86．64％。结论 分层抽样调查和线索调查并用在慢性丝虫病调查中具有实际意义。江苏省慢性丝虫病患病率仍较高，应积极开展慢性丝虫病治疗和照料工作。     

Clustered lot quality assurance sampling: a pragmatic tool for timely assessment of vaccination coverage

Objectives To evaluate oral poliovirus vaccine (OPV) coverage of the November 2009 round in five Northern Nigeria states with ongoing wild poliovirus transmission using clustered lot quality assurance sampling (CLQAS). Methods We selected four local government areas in each pre‐selected state and sampled six clusters of 10 children in each Local Government Area, defined as the lot area. We used three decision thresholds to classify OPV coverage: 75–90%, 55–70% and 35–50%. A full lot was completed, but we also assessed in retrospect the potential time‐saving benefits of stopping sampling when a lot had been classified. Results We accepted two local government areas (LGAs) with vaccination coverage above 75%. Of the remaining 18 rejected LGAs, 11 also failed to reach 70% coverage, of which four also failed to reach 50%. The average time taken to complete a lot was 10 h. By stopping sampling when a decision was reached, we could have classified lots in 5.3, 7.7 and 7.3 h on average at the 90%, 70% and 50% coverage targets, respectively. Conclusions Clustered lot quality assurance sampling was feasible and useful to estimate OPV coverage in Northern Nigeria. The multi‐threshold approach provided useful information on the variation of IPD vaccination coverage. CLQAS is a very timely tool, allowing corrective actions to be directly taken in insufficiently covered areas.     

From the Cover: Strong profiling is not mathematically optimal for discovering rare malfeasors

The use of profiling by ethnicity or nationality to trigger secondary security screening is a controversial social and political issue. Overlooked is the question of whether such actuarial methods are in fact mathematically justified, even under the most idealized assumptions of completely accurate prior probabilities, and secondary screenings concentrated on the highest-probablity individuals. We show here that strong profiling (defined as screening at least in proportion to prior probability) is no more efficient than uniform random sampling of the entire population, because resources are wasted on the repeated screening of higher probability, but innocent, individuals. A mathematically optimal strategy would be “square-root biased sampling,” the geometric mean between strong profiling and uniform sampling, with secondary screenings distributed broadly, although not uniformly, over the population. Square-root biased sampling is a general idea that can be applied whenever a “bell-ringer” event must be found by sampling with replacement, but can be recognized (either with certainty, or with some probability) when seen.