GUIDE PUBMED www ncbi nlm nih govpubmed PUBMED

GUIDE

PUBMED www. ncbi. nlm. nih. gov/pubmed

PUBMED OBJECTIVES OUTLINE OUTCOME Introducing Database Pub. Med What is Pub. Med Knowing Search Tools Pub. Med Search Boolean Operators Able to Combine Search Terms Me. SH Search Limits Able to Search in Pub. Med Search Engine Searching for Systematic Reviews Starch Strategy Me. SH Advantages of Me. SH Searching Clinical Queries

WHAT IS PUBMED? § produced by National Center for Biotechnology Information § includes MEDLINE, a biomedical database of worldwide journal literature in § § § medicine, nursing, dentistry, veterinary medicine, public health and the preclinical sciences is the most comprehensive bibliographic database of research articles on health/medicine topics citations index more than 5, 000 biomedical journals has more than 25 million citations from the 1940's to the present includes records of very recent articles and is updated each week is free to anyone with internet access includes SFX links to the journal publisher's web site which can provide the fulltexts of required documents

BOOLEAN OPERATORS Boolean operators (AND, OR and NOT) allow to combine search terms in different combinations. OR § searches for articles containing any of the chosen terms § combines synonyms, alterative spellings or related items § expands the results AND § searches for articles which contain all chosen terms § narrows the results NOT § excludes terms and must be used with caution to avoid excluding relevant items § excludes the second term from the results

SEARCH LIMITS Search limits allow to narrow to the specific aspects of a topic, such as: § article type choice – Meta-Analysis, Systematic Review § § § (quantitative summary combining results of independent studies), Clinical Trial, etc. human or animal studies male or female subjects age groups, for example adolescents, infants time periods languages

SEARCH STRATEGY 1 § Identifying search terms The aim is to identify the same concept in different ways and come up with a list of the different terms which can occur in the literature. § Searching with keywords Keywords are natural language, or free text words and phrases, that you enter into database search boxes. A keyword search looks for the search terms in the title and abstract of a reference in the database. § Truncation and wildcards can only be used when keyword searching, not when searching with subject headings. Truncation is useful for finding singular and plural forms of words and various endings. The database Pub. Med uses an asterisk * as its truncation symbol. E. g. typing therap* into a search box will find references containing any of these words: therapy, therapies, therapist or therapists. In Pub. Med, there is no particular symbol for searching keywords with a variant of a single character, such as a wildcard in some other databases

SEARCH STRATEGY 2 § Searching for the exact phrase If you want words to appear next to each other in an exact phrase, you should use one of the following formats: „kidney allograft“, kidneyallograft, kidney allograft[tw]. Phrase searching decreases the number of results and makes the results more relevant. § Searching with subject headings Records in Pub. Med have been assigned subject headings called Medical Subject Headings (Me. SH). When a search is carried out using Me. SH, you retrieve all records on a subject regardless of the terms used by the author.

Me. SH - MEDICAL SUBJECT HEADINGS § Me. SH is the National Library of Medicine's controlled vocabulary § § thesaurus used for indexing articles for the MEDLINE®/Pub. MED® database it imposes uniformity and consistency to the indexing of biomedical literature Me. SH terms are arranged in a hierarchical categorized manner called Me. SH Tree Structures and are updated annually each article is associated with a set of Me. SH terms that describe the content

ADVANTAGES OF Me. SH § searching using Me. SH allows to overcome problems of spelling and terminology § scope note indicates the meaning of the term § synonyms are organized under one Me. SH term § allows for both specific and comprehensive results § cuts down on irrelevant retrieval

Me. SH DATABASE

Me. SH Click to add to search builder. Subheadings describe specific aspects of the subject. Click if apropriate. Pick out the appropriate box to broaden or narrow the search for your interest.

CLINICAL QUERIES

SEARCHING CLINICAL QUERIES For evidence-based practice use the Clinical Queries option to find randomised controlled trials to answer a therapeutic question. Select Clinical Queries from the link on the home page and search as below:

RELATED LINKS § Pub. Med Tutorial www. nlm. nih. gov/bsd/disted/pubmedtutorial/cover. html § Pub. Med Help www. ncbi. nlm. nih. gov/books/NBK 3827/ § Searching the Evidence in Pub. Med www. library. medschl. cam. ac. uk/files/2015/10/Pub. Med-Aug 2015 -. pdf