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Literature searching. A literature search identifies relevant information sources that are used to answer clinical questions. PubMed searching. Search using keywords, text words, or subject headings PubMed looks for entered keywords or text words in each of the possible fields of a record
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Literature searching A literature search identifies relevant information sources that are used to answer clinical questions
PubMed searching • Search using keywords, text words, or subject headings • PubMed looks for entered keywords or text words in each of the possible fields of a record • e.g., author, title, abstract, journal name, volume, issue, date, etc. Evidence-based Chiropractic
Search dropdown list Features bar Query box Sidebar Evidence-based Chiropractic
PubMed homepage • Search terms are typed into the Query box • The Search drop-down list is typically left in its default position • The MeSH database can be searched from the Search drop-down list orusing a link in the sidebar Headache Evidence-based Chiropractic
PubMed sidebar The tutorial is excellent Link to the MeSH Database Clinical Queries link Evidence-based Chiropractic
PubMed sidebar (cont.) • The Clinical Queries link permits searches designed to answer clinical questions • Topics can be searched by clinical study categories (e.g., therapy, diagnosis, prognosis, etc.) • Or to only search for systematic reviews Evidence-based Chiropractic
PubMedClinical Queries search Search term Select study category Evidence-based Chiropractic
MANTIS • The MANTIS High Clinical Relevancy option is similar to PubMed’s Clinical Queries • High Clinical Relevancy limits a search to articles that involve clinical trials or case reports Evidence-based Chiropractic
MANTIS advanced search page MANTIS Advanced search screen Search term High Clinical Relevancy check box Evidence-based Chiropractic
PubMed Basic Search mode • Simply enter search terms in the Query box and click Go • PubMed produces a list of retrieved citations • Stopwordsare ignored by PubMed • e.g., the, and, because, thus, etc. • They don’t add or detract anything from the search results Evidence-based Chiropractic
Search results for chiropractic Click to see full citation Check box then click Display Evidence-based Chiropractic
Select format for display view Sort records by option Results can be sent Evidence-based Chiropractic
Multiple checkboxes • More than one record can be viewed at the same time by selecting the checkboxes next to the desired citations • Select a drop-down menu choice to set the display format • PubMed keeps track of checkboxes and displays all checked records when requested by clicking Display Evidence-based Chiropractic
Advanced PubMed search tactics • Limits • Click the Limits tab on the Features bar • Select the limiting search criteria from the screen that appears Evidence-based Chiropractic
More limit criteria Evidence-based Chiropractic
Limits (cont.) • Searching with limits will only retrieve articles that meet the limiting criteria that are set • Selecting from the Type of article menu limits searches to specific publication types • e.g., meta-analyses, clinical trials, case reports, editorials, etc. Evidence-based Chiropractic
Limits example • A search using the terms carpal tunnel syndrome without limits yields 5,728 citations―far too many to contend with • Whereas only 15 are retrieved when the following limits are set • English • Clinical Trial • Complementary Medicine Evidence-based Chiropractic
Field tags • Used to refine searches by forcing the query to consider specific search fields • Results are very similar to what is achieved using Limits • Thus, field tags are optional in PubMed • Some think field tags are easier to use and prefer them • Limits function is only partial in MANTIS Evidence-based Chiropractic
Field tags (cont.) • Field tags are placed within brackets after search terms • Does not matter how many spaces between the search term and the field tag • Does not matter whether upper or lower case letters are used • To usefield tags • Enter the search term in the query box followed by a field tag within brackets Evidence-based Chiropractic
Common PubMed Field Tags Evidence-based Chiropractic
Field tags example • If spinal stenosis is searched for in PubMed • Without any field tags, 2960 citations result • spinal stenosis • Using the Title Words [TI] field tag, only 731 • spinal stenosis [TI] • Combined with Author Name [AU], only 4 • spinal stenosis [TI] smith [AU] Evidence-based Chiropractic
Boolean (Logical) operators • Words that combine search terms to narrow down or broaden searches • Consist of AND, OR, and NOT • Should always be capitalized • Used by many databases, including PubMed and MANTIS Evidence-based Chiropractic
Boolean operator AND • AND limits or narrows down a search • Combines terms so that only citations that contain both terms are retrieved • For example • A PubMed search for sacroiliac joint yields 2,760 citations and manipulation 33,819 • Searching sacroiliac joint AND manipulation narrows the results down to 76 Evidence-based Chiropractic
AND example sacroiliac joint2,760 citations manipulation33,819 citations sacroiliac joint AND manipulation76 citations Evidence-based Chiropractic
Combining more than 2 terms sacroiliacmanipulation joint chiropractic sacroiliacjointAND manipulation ANDchiropractic 18 citations Evidence-based Chiropractic
Boolean operator OR • OR expands a search • All articles that contain either of the queried terms are retrieved • For example • Searching PubMed for sacroiliac joint OR manipulation expands the results to 36,503 • OR is useful when searching for different versions of a word • e.g., manipulation OR adjustment Evidence-based Chiropractic
OR example sacroiliac joint2,760 citations manipulation33,819 citations sacroiliac joint OR manipulation 36,503 citations Evidence-based Chiropractic
Boolean operator NOT • NOT also limits or narrows down a search • Only retrieves citations that do include the first term, but do not include the second term • For example • Searching PubMed for sacroiliac joint NOT manipulation narrows down the number of citations from 2,760 to 2,684 • 76 articles include manipulation and the SI joint, so they are eliminated Evidence-based Chiropractic
NOT example sacroiliac joint NOT manipulation sacroiliac manipulation joint Articles that include both sacroiliac joint and manipulation are eliminated Evidence-based Chiropractic
Nesting • Controls the order in which PubMed processes search terms • From left to right by default • Search terms are enclosed in parentheses • Terms within the parentheses are processed first • Boolean operators can be included Evidence-based Chiropractic
Nesting example • If a doctor wants information on the non-surgical treatment of carpal tunnel syndrome, the query might look like this • carpal tunnel syndrome AND (treatment NOT surgery) • This search will locate articles that deal with treatment, but not those that involve surgery Evidence-based Chiropractic
Nesting example 2 • Searching chiropractic AND (whiplash OR chronic pain) • The database will first find all references that contain whiplash plus those that contain chronic pain • Then it will restrict results to those that also contain the word chiropractic Evidence-based Chiropractic
The AND operator is used between words by default • PubMed searches for headache AND therapy exactly the same way as headachetherapy • Thus, AND is sometimes optional • To see how PubMed performed a search • Click the Details tab after the search is complete • Read the Query Translation Evidence-based Chiropractic
Details tab Translation is exactly the same when AND is used Evidence-based Chiropractic
Query Translation • Useful in figuring out why an unproductive search failed • Also to plan a subsequent search strategy that will be more successful Evidence-based Chiropractic
Automatic Term Mapping • When terms are searched without a field tag, they are matched (in order) against the • MeSH Translation Table • Journals Translation Table • Full Author Translation Table • Author Index Evidence-based Chiropractic
Automatic Term Mapping (cont.) • If the term matches a MeSH term, it is searched both as a MeSH term and a Text Word • The Journals Translation Table yields an abbreviated title when the journal’s full title is searched • Journal of the American Medical Association • JAMA or J Am Med Assoc Evidence-based Chiropractic
Automatic Term Mapping (cont.) • The Full Author Translation Table retrieves the author’s full name • Only for articles published after 2001 • Order of names doesn’t matter • Searching meeker william c is equivalent to william cmeeker • Commas are not necessary • Helpful to distinguish first from last names (e.g., John James) Evidence-based Chiropractic
Truncation (a.k.a, wildcard search) • Search for various uses of the same root word • The root word verte can be expanded to vertebra, vertebrae, vertebral, etc. • Searching only vertebral misses other forms of the word • The root word with an asterisk retrieves all forms of the word • e.g., verte* Evidence-based Chiropractic
Truncation (cont.) • An * can be placed at the beginning or end of search terms • An * can also be placed within a word when a letter is variable or absent • The search term an*emia will look for anemia and anaemia • analy*e will look for analyze and analyse Evidence-based Chiropractic
Phrase searching • Forces PubMed to search for a phrase rather than individual terms • Only the exact phrase will be queried • The phrase must be placed within quotation marks • A search of intervertebral disc herniation produces 11,747 citations • Whereas“intervertebral disc herniation” produces only 183 Evidence-based Chiropractic
Medical Subject Headings (MeSH) • A list of vocabulary terms used to index medical literature • Developed by the National Library of Medicine (NLM) • MeSH terms are assigned to all MEDLINE records by NLM indexers corresponding to the article’s major topics Evidence-based Chiropractic
Finding MeSH terms • Select MeSH from the drop-down list next to the Search button on the PubMed homepage • Enter term in PubMed query box • A list of the MeSH terms or alternative suggestions will appear Evidence-based Chiropractic
Enter term Select MeSH Evidence-based Chiropractic
No terms found Suggested terms Click likely terms Evidence-based Chiropractic
List of MeSH terms (only one in this case) Evidence-based Chiropractic
Finding MeSH terms (cont.) • Another way to find MeSH terms is to view thecitation format of an article • Click Citation from the drop-down list next to the Display button located at the top and bottom of each page of retrieved records Evidence-based Chiropractic
Select Citation Check the articles of interest Evidence-based Chiropractic
The complete citation appears Including a list of MeSH terms Evidence-based Chiropractic