Sometimes a search can be overly general (results equal too many hits) or overly specific (results equal too few hits). To fine tune your search, you can use AND, OR, and NOT operators to link your search words together. These operators will help you narrow or broaden your search to better express the terms you are looking for and to retrieve the exact information you need quickly.
USING THE "AND" OPERATOR: If you have a search term that is too general, you can append several terms together using "AND." By stringing key terms together, you can further define your search and reduce the number of results. Note: Unless you define a specific search field, the result list will contain references where all your search terms are located in either the citation, full display or full text.
• For example, type high risk AND injury to find only articles that reference high risk injuries.
USING THE "OR" OPERATOR: In order to broaden a search, you can link terms together by using the "OR" operator. By using "OR" to link your terms together you can find documents on many topics. Linked by this operator, your words are searched simultaneously and independently of each other.
• As an example, search high risk AND injury OR trauma to find results that contain either the terms "high risk" and "injury," or the term "trauma."
USING THE "NOT" OPERATOR: In order to narrow a search, you can link words together by using the "NOT" operator. This operator will help you to filter out specific topics you do not wish included as part of your search.
Parentheses also may be used to control a search query. Without parentheses, a search is executed from left to right. Words that you enclose in parentheses are searched first. Why is this important? Parentheses allow you to control and define the way the search will be executed. The left phrase in parentheses is searched first; then based upon those results the second phrase in parentheses is searched.
Generalized Search: heart or lung and blood or oxygen Focused Search: (heart or lung) and (blood or oxygen)
In the first example, the search will retrieve everything on "heart" as well as references to the terms "lung" and "blood," and everything on "oxygen."
In the second example, we have used the parentheses to control our query to only find articles about heart or lung that reference blood or oxygen.
Using the entry date field (EM), you can narrow the search to a specific date. To search the most current articles of the database, the entry date field code is essential. For example,
• Type: critical care and EM 201207
In the example above, the entry month field will produce only results concerning critical care entered into the database in July 2012. Note: you can use a hyphen to indicate an open-ended date range. Entering a hyphen either before or after an entry month will find results "on or before" or "on or after" the date entered.
The Evidence-based practice journal subset is applied to articles from evidence based practice journals (including Cochrane), as well as articles about evidence based practice, research articles (including systematic reviews, clinical trials, meta analyses, qualitative studies), commentaries on research studies (applying practice to research), case studies if they meet the criteria of the use of research and/or evidence based practice terms.
You can refine your search using specific search strategies designed to narrow your results in five research areas, Therapy, Prognosis, Review, Qualitative, and Causation (Etiology). Three strategies are provided for each area. High Sensitivity - the broadest search to include ALL relevant material. It may include less relevant materials. High Specificity - the most targeted search to include only the most relevant result set, may miss some relevant materials. Best Balance - retrieves the best balance between Sensitivity and Specificity.
Clinical Queries are created in collaboration with the Health Information Research Unit (HIRU) at McMaster University, and are designed for clinician use.
The publication authority file is an alphabetical list of the journal titles included in this database. Any publication found in the product's data will be listed in this authority file. As a result, any exclusive search of a publication in this list is guaranteed to create results.