iCite Database Snapshot 2021-11

This is a database snapshot of the iCite web service (provided here as a single zipped CSV file, or compressed, tarred JSON files). In addition, citation links in the NIH Open Citation Collection are provided as a two-column CSV table in open_citation_collection.zip. iCite provides bibliometrics and metadata on publications indexed in PubMed, organized into three modules: Influence: Delivers metrics of scientific influence, field-adjusted and benchmarked to NIH publications as the baseline. Translation: Measures how Human, Animal, or Molecular/Cellular Biology-oriented each paper is; tracks and predicts citation by clinical articles Open Cites: Disseminates link-level, public-domain citation data from the NIH Open Citation Collection Definitions for individual data fields: pmid: PubMed Identifier, an article ID as assigned in PubMed by the National Library of Medicine doi: Digital Object Identifier, if available year: Year the article was published title: Title of the article authors: List of author names journal: Journal name (ISO abbreviation) is_research_article: Flag indicating whether the Publication Type tags for this article are consistent with that of a primary research article relative_citation_ratio: Relative Citation Ratio (RCR)--OPA's metric of scientific influence. Field-adjusted, time-adjusted and benchmarked against NIH-funded papers. The median RCR for NIH funded papers in any field is 1.0. An RCR of 2.0 means a paper is receiving twice as many citations per year than the median NIH funded paper in its field and year, while an RCR of 0.5 means that it is receiving half as many citations per year. Calculation details are documented in Hutchins et al., PLoS Biol. 2016;14(9):e1002541. provisional: RCRs for papers published in the previous two years are flagged as "provisional", to reflect that citation metrics for newer articles are not necessarily as stable as they are for older articles. Provisional RCRs are provided for papers published previous year, if they have received with 5 citations or more, despite being, in many cases, less than a year old. All papers published the year before the previous year receive provisional RCRs. The current year is considered to be the NIH Fiscal Year which starts in October. For example, in July 2019 (NIH Fiscal Year 2019), papers from 2018 receive provisional RCRs if they have 5 citations or more, and all papers from 2017 receive provisional RCRs. In October 2019, at the start of NIH Fiscal Year 2020, papers from 2019 receive provisional RCRs if they have 5 citations or more and all papers from 2018 receive provisional RCRs. citation_count: Number of unique articles that have cited this one citations_per_year: Citations per year that this article has received since its publication. If this appeared as a preprint and a published article, the year from the published version is used as the primary publication date. This is the numerator for the Relative Citation Ratio. field_citation_rate: Measure of the intrinsic citation rate of this paper's field, estimated using its co-citation network. expected_citations_per_year: Citations per year that NIH-funded articles, with the same Field Citation Rate and published in the same year as this paper, receive. This is the denominator for the Relative Citation Ratio. nih_percentile: Percentile rank of this paper's RCR compared to all NIH publications. For example, 95% indicates that this paper's RCR is higher than 95% of all NIH funded publications. human: Fraction of MeSH terms that are in the Human category (out of this article's MeSH terms that fall into the Human, Animal, or Molecular/Cellular Biology categories) animal: Fraction of MeSH terms that are in the Animal category (out of this article's MeSH terms that fall into the Human, Animal, or Molecular/Cellular Biology categories) molecular_cellular: Fraction of MeSH terms that are in the Molecular/Cellular Biology category (out of this article's MeSH terms that fall into the Human, Animal, or Molecular/Cellular Biology categories) x_coord: X coordinate of the article on the Triangle of Biomedicine y_coord: Y Coordinate of the article on the Triangle of Biomedicine is_clinical: Flag indicating that this paper meets the definition of a clinical article. cited_by_clin: PMIDs of clinical articles that this article has been cited by. apt: Approximate Potential to Translate is a machine learning-based estimate of the likelihood that this publication will be cited in later clinical trials or guidelines. Calculation details are documented in Hutchins et al., PLoS Biol. 2019;17(10):e3000416. cited_by: PMIDs of articles that have cited this one. references: PMIDs of articles in this article's reference list. Large CSV files are zipped using zip version 4.5, which is more recent than the default unzip command line utility in some common Linux distributions. These files can be unzipped with tools that support version 4.5 or later such as 7zip. Comments and questions can be addressed to [e-mail]

本数据集为iCite网络服务的数据库快照，以单个压缩CSV文件或压缩打包的JSON文件形式提供。此外，美国国立卫生研究院（National Institutes of Health，NIH）开放引用集（NIH Open Citation Collection）的引用链接以两列CSV表格的形式存放在`open_citation_collection.zip`中。

iCite可为PubMed收录的文献提供文献计量学指标与元数据，分为三大模块：
1. **影响力（Influence）**：提供经领域校正、以NIH资助文献为基准的科学影响力计量指标；
2. **翻译倾向性（Translation）**：量化单篇文献偏向人类、动物或分子/细胞生物学的程度，并追踪、预测临床类文献的引用情况；
3. **开放引用（Open Cites）**：公开传播来自NIH开放引用集的链接级公共领域引用数据。

### 各数据字段定义
- `pmid`：PubMed标识符（PubMed Identifier），即美国国立医学图书馆在PubMed中分配的文献唯一ID；
- `doi`：数字对象标识符（Digital Object Identifier，DOI），若文献可获取则提供对应值；
- `year`：文献正式发表的年份；
- `title`：文献标题；
- `authors`：作者姓名列表；
- `journal`：期刊名称（采用ISO缩写格式）；
- `is_research_article`：标记字段，用于指示该文献的出版类型标签是否符合原创研究文章的定义；
- `relative_citation_ratio`：相对引用率（Relative Citation Ratio，RCR）——美国国立卫生研究院办公室（OPA）开发的科学影响力计量指标。该指标经领域与时序双重校正，以NIH资助文献为基准。任意领域内NIH资助文献的RCR中位数为1.0：RCR为2.0意味着该文献每年获得的引用量为其所属领域、同年度NIH资助文献中位数的2倍，而RCR为0.5则表示每年获得的引用量仅为该基准的一半。该指标的详细计算方法参见Hutchins等发表于*PLoS Biology* 2016;14(9):e1002541的研究；
- `provisional`：近两年发表的文献的RCR会被标记为「暂定型」，以反映新近发表文献的引用计量指标稳定性弱于旧文献。若上一年度发表的文献获得至少5次引用，即使其发表时长不足一年，也会提供暂定型RCR；所有上上年发表的文献均会提供暂定型RCR。当前年度采用美国国立卫生研究院财年定义（起始于每年10月）。例如，2019年7月（NIH 2019财年），2018年发表且引用量≥5次的文献将被标记为暂定型RCR，且2017年发表的所有文献均会提供暂定型RCR；2019年10月（NIH 2020财年起始），2019年发表且引用量≥5次的文献将被标记为暂定型RCR，且2018年发表的所有文献均会提供暂定型RCR；
- `citation_count`：引用该文献的唯一文献总数量；
- `citations_per_year`：该文献自发表以来每年平均获得的引用量。若该文献同时以预印本和正式发表版本形式发布，则以正式发表版本的年份作为主要发表日期。该指标为相对引用率的分子项；
- `field_citation_rate`：基于该文献的共引网络估算得到的所属领域固有引用率；
- `expected_citations_per_year`：与该文献具有相同领域引用率且发表于同一年度的NIH资助文献每年平均获得的引用量。该指标为相对引用率的分母项；
- `nih_percentile`：该文献的RCR在所有NIH资助文献中的百分位排名。例如，95%意味着该文献的RCR高于95%的NIH资助文献；
- `human`：该文献中属于人类、动物或分子/细胞生物学类别的医学主题词（MeSH terms）中，归为人类类别的占比；
- `animal`：该文献中属于人类、动物或分子/细胞生物学类别的医学主题词中，归为动物类别的占比；
- `molecular_cellular`：该文献中属于人类、动物或分子/细胞生物学类别的医学主题词中，归为分子/细胞生物学类别的占比；
- `x_coord`：该文献在生物医学三角图（Triangle of Biomedicine）上的X轴坐标；
- `y_coord`：该文献在生物医学三角图上的Y轴坐标；
- `is_clinical`：标记字段，用于指示该文献符合临床类文献的定义；
- `cited_by_clin`：引用该文献的临床类文献的PubMed标识符列表；
- `apt`：近似翻译潜能（Approximate Potential to Translate，APT）是基于机器学习的估算值，用于预测该文献后续被临床试验或临床指南引用的可能性。该指标的详细计算方法参见Hutchins等发表于*PLoS Biology* 2019;17(10):e3000416的研究；
- `cited_by`：引用该文献的所有文献的PubMed标识符列表；
- `references`：该文献参考文献列表中收录的文献的PubMed标识符列表。

大型CSV文件采用zip 4.5版本压缩，该版本较部分常见Linux发行版默认的unzip命令行工具更新。可使用支持zip 4.5及以上版本的解压工具（如7zip）进行解压。如有疑问或建议，请发送邮件至[e-mail]。