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As TWU students in the field of health science, your work will need to be based upon solid research:
Evidence-based medicine (EBM) is an approach to medical practice intended to optimize decision making by emphasizing the use of evidence from well-designed and well-conducted research.
As future professions, you will be required to continue your professional development:
“One of the responsibilities of any professional is to maintain expertise, and this responsibility is probably nowhere more critical, or more difficult, than in the profession of medicine"
(Laine & Weinberg, 1999)
“In 1980, the biomedical literature was estimated to be expanding at a compound rate of 6% - 7% per annum, doubling every 10 to 12 years. based on an estimated rate of 200,000 biomedical publications per annum in 1979, it was determined that if clinicians read two articles per day every day for a year, by the end of the year they would be 55 centuries behind”
(Cook et al., 1996)
Therefore, as you will be stuck looking for articles anyway--learning how to search effectively now--will save you a lot of work later.
Subject headings A subject heading search will search for articles on a given subject rather than by keywords.
Not all databases use the same subject heading catalog. The most widely featured subject heading catalog is MeSH (Medical Encyclopedia of Subject Headings).
Pro's: The main advantage of a subject heading search is that all articles produced should all be about the subject you have selected. In theory, you should receive more pertinent, albeit fewer, results than a keyword search.
Con's: The main disadvantage of a subject heading search is that it will not always produce the most recent literature a database has to offer. Because of the high volume of medical literature coming out every week, most databases, if not all, are several months behind in cataloging articles. Until articles have been cataloged they will not show up on a subject heading search.
Conducting a Subject Heading search on PubMed.
Step 1. How to select MeSH on Pubmed
Step 2. Beginning a search on Mesh
Step 3. Selecting sub categories and narrowing down your search.
Step 4. How to add a second concept to your search.
Keyword searches will look through the text of an article for whatever word/s you have specified.
Pro's: The database will look everywhere within the article for your keyword. One benefit of this is that you can use natural language. A keyword search will typically produce more results than a subject heading search. Allows for the use of boolean operators, phrases, and field searches.
Con's: More results to sift through and many of these results can be less relevant than a subject heading search.
Boolean Operators: AND, OR, & NOT
The AND Boolean operator will reduce the amount of results a search yields as it forces the database to be more specific. For example, here the database will only return results that feature both the terms "heart attack" AND aspirin.
TIP* If you have too many results to wade through...try using an additional search concept with AND to get a smaller, more specific, batch of results.
The OR Boolean operator should return mORe results. OR is useful for adding synonyms or alternate words to your search.
The NOT Boolean operator will purposefully exclude articles containing the specified search term/s.
NOT can be used to narrow down the desired meaning of a term that has different connotative meanings.
Use the NOT Boolean operator with care. You might lose the perfect article because it randomly mentioned the term you excluded. If you need to reduce the amount of results your search yields first try thinking of another search term and adding it to your search with an AND.
Putting phrases in quotes can make a huge difference to your search! In the examples below you can see that in picture 1, the phrase 'peanut butter and jelly day' was not placed in quotations and Google scholar brought back 27,100 results of which 99% were not pertinent. In the second picture the phrase was placed in quotations and only 23 results came back, but all were pertinent.
Warning When you put a phrase into quotations the database will search for exactly that phrase, e.g. a search for aspirin vs tylenol will fail to bring back articles where the author phrased this differently--tylenol vs aspirin or aspirin versus tylenol.
Note* Some databases, e.g. Ovid Psychinfo will not accept quotation marks.
You can add the truncation asterisk/symbol ( * ) to the root of a word in order to come up with all the possible endings--thereby saving you the time of entering them all in yourself. Be careful of cutting the word too short as this might open the search up to irrelevant search results.
The wildcard symbol (usually a "#" or "?") can be substituted in place of individual character/s in a term. This can be useful if you are not sure of the correct spelling of a word. However, it is mostly used to produce multiple forms of a term without having to enter that term multiple times,
Example: wom?n retrieves woman or women
Most databases allow users to limit their search by certain criteria, hence the name limiters. Limiters are usually found under the advanced search option and/or on the left hand side of the screen.
Using limiters in Pubmed: Step 1.
Using limiters in Pubmed: Step 2.
Using limiters in Pubmed: Step 3.
Fields, are allocated spaces within a database that are set up to store a specific type of information about a given article, e.g. the author field will be where author names are stored. Field searching allows you to tell a database exactly where you want to look for your keywords.
Field searches are helpful if:
You want articles that that specifically mention your keywords in the abstract field or title field to narrow down your results or make them more relevant.(title/abstract field).
You are looking for a specific author (author field).
You want to find a specific article but can only remember a word or two of the title (title field).
You want to pinpoint a particular subject (subject field).
You want articles that specifically mention your keywords in their abstract (abstract field).
Field searching in PubMed: Step 1.
Field searching in PubMed: Step 2.
Field searching in PubMed: Step 3.
TIP* if the author has thought enough of your selected keyword that he/she has included it in the title of his/her article--then the chances are that this article will be very pertinent to your information needs
Strategies to narrow down the number of results in a keyword search:
Strategies to broaden up the number of results in a keyword search: