Expand and reduce the number of results
A successful search ends with displaying all relevant results with a minimum of irrelevant results (“noise”).
The ability to perform a successful search depends on the database, yet also on the user, who needs to choose the correct words and the syntax between them (the “search query”). The searcher has a number of options, which are designed to help reduce the number of results in case of excess noise or to expand the number of results obtained, with the aim of including as many relevant results as possible.
| Signs | Result and Meaning |
|---|---|
|
Write two words in sequence without special signs act like "And". |
Used to reduce the number of results. |
|
Use double quotation marks that surround the search terms (" "). |
You get results that contain the exact phrase. For example: “breast cancer”. Used to reduce the number of results. |
|
Use a question mark (?) to replace one character. Used for including single, multiple, active and passive in the same search. |
Example: nurse? You get results with the words nurses, nursed. Used to increase the number of results. |
|
Use an asterisk (*) to replace several characters, at the end of a word and sometimes at the beginning and at the middle. |
Example: epidemiologist* for - epidemiology, epidemiological– epidemiologist. Used to increase the number of results. |
Boolean Operators – for one smart search that prevents multiple searches
The linking words AND, OR, NOT (and by their professional name “Boolean Operators”) allow a combination of words to optimize the search:
AND
- Reduces the number of results.
- The results include both words.
- The search engine ignores records containing only one of the words.
NOT
- Reduces the number of results.
- The results will show records in which only the first term appear and not the second term.
- Recommended only when there is no other choice.
OR
- Increases the number of results.
- The results will show records in which the first or the second term appear or both.
- Used in the case of synonyms.
Other options to reduce the number of results:
- Focus on specific fields – for example, search for words only in titles, topics, etc.
- Year Range – limit the search results to those published between year ranges (e.g., last 5 years).
- Reduce topics – in some databases you can choose other options such as research type, age groups, topics and more.