Keyword is a highly refined content of the paper, which can reveal the theme of the paper and has practical retrieval significance. Keywords are commonly used retrieval languages on the Internet at present, and are widely used by literature retrieval tools and academic journals. Therefore, whether the keyword index is appropriate directly affects the collection of papers in the database and the retrieval and utilization of readers, thus affecting the precision and recall of papers, and the scientific research results cannot be effectively disseminated and utilized. For periodicals, it will reduce the citation rate and influencing factors of periodicals.
I. Overview
Keywords include subject words, sub-subject words and free words. Subject words are standard keywords, also known as descriptors, and are a specially designed artificial retrieval language. Subject words are more specific and standardized than keywords, and have a stronger correlation with literary themes. Subject words can be keywords, but keywords are not necessarily subject words.
Free words are keywords that are not subject words, but relatively free keywords. Different from subject words, they are often words that are not included in the thesaurus or have no suitable superordinate words. Although there are no fixed standards for the choice of free words, they are not randomly selected, and there are still some relevant norms. Therefore, when indexing medical papers with keywords, the choice of free words still needs to be cautious.
Second, the significance of keyword indexing
1 reflects the theme of literature.
Keywords can express the theme of the paper intuitively, and are the window for readers to understand the main content of the paper, so that readers can see the theme of the paper at a glance before reading the abstract and text of the paper, so as to quickly determine whether the paper is of reading value to themselves.
2, easy to search and use
Keyword is the most important retrieval language on the Internet at present, and it is the best way to index the document information by computer, especially suitable for the information processing of massive documents under the network environment. Therefore, it is widely used by literature retrieval tools, and it is also the most commonly used retrieval item in our usual literature retrieval.
Third, the index of keywords.
1, keyword selection
The selection of key words in the paper should be based on the title, abstract, subtitle in the text and words and/or phrases that can accurately reflect the theme of the paper. The paper format network mainly includes the main words that appear in the title, abstract or text of the paper, and the words that frequently appear in the text can reflect the nature, purpose and means of the manuscript. As far as medical papers are concerned, the names of medical terms or phrases such as diseases, syndromes, therapies, prescriptions, drugs, acupoints, doctors, treatises, biochemical indicators, etc. can all be used as keywords. These keywords can be narrative words or free words. Traditional Chinese medicine can refer to the Thesaurus of Traditional Chinese Medicine edited by Institute of Information, Chinese Academy of Traditional Chinese Medicine.
When indexing keywords, subject words take precedence. If you can't find the corresponding words or phrases in the thesaurus, or the subject words can't fully express the subject content, you can choose the most suitable free words. Attention should be paid to the use of standard medical terms and the conversion between natural language and subject language when indexing. The common forms of topic conversion are as follows: ① Proverbs, abbreviations and code names in literature need to be standard medical vocabulary before they can be converted into medical subject words or free words. ② Abbreviations of some disease names or diagnostic techniques in literature should be converted into subject words.
2, the order and quantity of keywords
The number of keyword indexing directly affects the degree of revealing the theme of the paper. According to GB77 13-87, the number of keywords to be selected for each paper is 3-8. Generally speaking, the more keywords, the deeper the theme of the article is revealed, the more detailed the content is reflected, and the narrower the search scope is defined. If there are too many indexes, it will lead to too many indexes or duplicate indexes; On the other hand, the less keyword indexing, the broader the definition of the search scope and the less profound the disclosure of the theme, which will easily lead to incomplete expression of the theme concept, or omission of some valuable information points, resulting in fewer or missing marks. Therefore, proper indexing is very important for the accurate expression of the theme of the paper, and keyword indexing should balance the precision and recall of the paper, which can not only locate the paper in a specific category, but also accurately reveal the theme of the paper. The specific number of keyword indexing needs to be determined according to the number of theme concepts in the article.
The order of keywords should be in descending order of importance. Generally, the key keywords that express the opinions and contents of the article are put in the first place. The key words that reflect the research purpose, object, method and process of the paper rank first, and the key words that reveal the research results, significance and value rank last. In the same semantic field, the superordinate word comes first and the subordinate word comes last; The keywords that express the same category should be relatively concentrated and try to get together.
3. Preventive measures
Don't use common words. General words refer to those general words that have no independent retrieval meaning, can't express the theme attribute and can't reflect the essence of the content. The terms "method", "observation", "problem", "theory", "report", "experiment", "research", "analysis" and "report" are applicable to different disciplines, and the format of the paper as a key word has no reference value and retrieval significance. If these words are used as keywords to index, it will lack the specificity of the thesis theme, which will often lead to false detection of the literature. The retrieval results will bring together irrelevant documents from different disciplines, forming a bunch of messy and useless junk information, which will seriously reduce the precision rate of papers.
② Meaningless words such as pronouns, articles, conjunctions and interjections, as well as adverbs, adjectives and some verbs should not be used.
③ Don't use formulas. Such as chemical structural formula, chemical reaction formula and mathematical formula.
English abbreviations and symbols should not be used, even though they have been widely used.
⑤ Avoid using phrases with many qualifiers. Related suggestions: