Counts of Dengue without warning signs reported in HONDURAS: 1978-2005

Project Tycho datasets contain case counts for reported disease conditions for countries around the world. The Project Tycho data curation team extracts these case counts from various reputable sources, typically from national or international health authorities, such as the US Centers for Disease Control or the World Health Organization. These original data sources include both open- and restricted-access sources. For restricted-access sources, the Project Tycho team has obtained permission for redistribution from data contributors. All datasets contain case count data that are identical to counts published in the original source and no counts have been modified in any way by the Project Tycho team. The Project Tycho team has pre-processed datasets by adding new variables, such as standard disease and location identifiers, that improve data interpretabilty. We also formatted the data into a standard data format.Each Project Tycho dataset contains case counts for a specific condition (e.g. measles) and for a specific country (e.g. The United States). Case counts are reported per time interval. In addition to case counts, datsets include information about these counts (attributes), such as the location, age group, subpopulation, diagnostic certainty, place of aquisition, and the source from which we extracted case counts. One dataset can include many series of case count time intervals, such as "US measles cases as reported by CDC", or "US measles cases reported by WHO", or "US measles cases that originated abroad", etc.Depending on the intended use of a dataset, we recommend a few data processing steps before analysis:- Analyze missing data: Project Tycho datasets do not inlcude time intervals for which no case count was reported (for many datasets, time series of case counts are incomplete, due to incompleteness of source documents) and users will need to add time intervals for which no count value is available. Project Tycho datasets do include time intervals for which a case count value of zero was reported.- Separate cumulative from non-cumulative time interval series. Case count time series in Project Tycho datasets can be "cumulative" or "fixed-intervals". Cumulative case count time series consist of overlapping case count intervals starting on the same date, but ending on different dates. For example, each interval in a cumulative count time series can start on January 1st, but end on January 7th, 14th, 21st, etc. It is common practice among public health agencies to report cases for cumulative time intervals. Case count series with fixed time intervals consist of mutually exxclusive time intervals that all start and end on different dates and all have identical length (day, week, month, year). Given the different nature of these two types of case count data, we indicated this with an attribute for each count value, named "PartOfCumulativeCountSeries".

第谷项目（Project Tycho）数据集收录全球各国上报的各类疾病的病例统计数据。第谷项目数据编审团队从各类权威来源提取上述病例数，此类来源通常为国家或国际卫生主管部门，例如美国疾病控制与预防中心（US Centers for Disease Control）与世界卫生组织（World Health Organization）。上述原始数据源涵盖开放获取与受限访问两类；针对受限访问数据源，第谷项目团队已获得数据贡献方的再分发许可。
所有数据集均完整保留与原始发布源完全一致的病例数，第谷项目团队未对任何病例数进行修改。团队已对数据集完成预处理，新增了可提升数据可解释性的标准化疾病与位置标识符等新变量，并将数据统一格式化为标准数据格式。
每个第谷项目数据集对应特定病种（如麻疹（measles））与特定国家（如美国（The United States）），病例数按时间间隔进行上报。除病例数外，数据集还包含此类计数的相关属性信息，例如地点、年龄组、亚人群、诊断确定性、感染来源以及病例数提取来源等。一个数据集可包含多组病例数时间序列，例如"美国疾病控制与预防中心上报的美国麻疹病例数""世界卫生组织上报的美国麻疹病例数""境外输入性美国麻疹病例数"等。
根据数据集的使用用途，我们建议在开展分析前完成若干数据处理步骤：
1. 处理缺失数据：第谷项目数据集未包含无病例数上报的时间区间（部分数据集的病例数时间序列因源文档不完整而存在缺失，用户需自行补充无计数的时间区间）；但数据集已包含病例数为0的时间区间。
2. 区分累积型与非累积型时间序列：第谷项目数据集中的病例数时间序列可分为"累积型"与"固定间隔型"。累积型病例数时间序列包含起始日期相同但结束日期不同的重叠区间，例如某累积计数序列的所有区间均始于1月1日，结束日期分别为1月7日、14日、21日等。公共卫生机构通常会采用累积时间区间上报病例数。固定间隔型病例数序列则包含互不重叠的时间区间，所有区间的起止日期均不同且时长一致（如日、周、月、年）。鉴于两类病例数数据的本质差异，我们已为每个计数值新增名为"PartOfCumulativeCountSeries"的属性以标注其类型。