Search Techniques
Several search techniques are common to a variety of licensed databases - subject headings, truncation, Boolean operators, and limits. Depending on your topic, there may also be search filters available to apply to one or more databases. See these Medline Ovid tutorials for an overview.
You may find it helpful to use a table in Word or Excel to track the subject headings and keywords you've used for concepts. Also, most licensed databases include an option to save your search history, and to set up email alerts when new articles are found on your topic.
Keep Track of Your Research
Keep Track of Your Searches
Recording information about your searches and search results is essential and will keep you from unnecessary repetition and provide critical information to anyone you ask for assistance with your search.
Here's an example:
| Database | Date | Search Terms | Limits/Filters |
Results & Comments |
Database Terminology |
Database Term Search |
Results & Comments |
|---|---|---|---|---|---|---|---|
| Web of Science | 2020/01/20 |
exoskeleton and rehabilitation |
none |
2,455 Powered and non-powered came up in search |
exoskeleton robot; rehabilitation robots |
("exoskeleton robot*" OR "rehabilitation exoskeleton" OR "rehabilitation robot") AND (gait* OR "gait analysis") |
564 |
|
Compendex Engineering Village, etc. |
2020/02/08 |
Subject Headings
Many databases include a system of subject headings (which may also be called descriptors). These terms are added to articles by human indexers to make it easier to search for all the articles on a particular concept. MeSH (Medical Subject Headings) are used in MEDLINE. EMBASE, CINAHL, and many other databases have their own systems of subject headings; these can usually be found in the thesaurus section of a database.
Keywords
For a thorough literature search, you should search with both keywords and subject headings. Some databases or grey literature search sources only allow searching by keyword. A useful technique to utilize in keyword searching is truncation (or wildcards). This is when you use a character at the end or within a word to search for different spellings. Many databases use * as the truncation symbol.
- Example: rehab* searches for rehabilitation, rehabilitate, rehabilitating... anything that begins with "rehab".
Most databases support searching for exact phrases by putting words in quotes.
Some databases allow adjacency searching, which will find words close to each other, but in any order.
- Example: In Ovid MEDLINE, spinal cord adj3 injury will find the words spinal cord and injury within 3 words of each other. If a paper uses injury to the spinal cord, it will be found as well as spinal cord injury
Check the Help ? section of the database you're using to find out which of these features are available and how to use them.
Some of the UBC article databases and their functions can be found on the Truncation and Wildcard Symbols page.
Boolean Operators
Boolean operators are useful for combining subject headings and keywords.
- Example: Stroke AND balance finds articles with both these concepts
- Example: Stroke OR CVA finds articles that include either or both concepts
NOT is another operator which will find one concept while excluding another. Use with caution because you may exclude relevant articles this way.
Limit or Refine
Most databases include various limiters. These usually qualify human characteristics such as gender, ethnicity or age or publication characteristics such as language, publication date, study design, or type of publication.
One way to limit to human studies in Ovid MEDLINE is to combine this line with the last set of your search:
NOT (exp animals/ NOT (exp animals/ AND humans/)