Once you have determined what your research question is and where you think you should search, you need to translate your question into a useable search. Doing so will:
If you need to explore a topic first, your search strategy can initially be quite loose. You can then revisit search terms and update your search strategy accordingly. Record your search strategy as you develop it and capture the final version for each place that you search.
Remember that information retrieval in the area of food is complex because of the broadness of the field and the way in which content is indexed. As a result, there is often a high level of ‘noise’ when searching food topics in a database not designed for food content. Creating successful search strategies involves knowledge of a database, its scope, indexing and structure.
Shaping a search strategy
A good search strategy will include:
Using a search matrix helps you brainstorm and collect words to include in your search. To populate a search matrix:
Note: You don’t need to fill all of the boxes in a search matrix.
You will find that you need to do some searches as you experiment in running it and this will help you refine your search strategy. For the search on this example question:
See the revised matrix (after running searches) tab!
This revised matrix shows both adjustments made to terms, and how the terms are connected with Boolean operators. Different forms of the same concept (the columns) are connected with OR, and each of the different concepts are connected with AND.
Boolean operators tell a database or search engine how the terms you type are related to each other.
Use OR to connect variations representing the same concept. In many search interfaces you will want to put your OR components inside parentheses like this: (safe OR “food safety” OR decontamination OR contamination OR disinfect*). These are now lumped together into a single food safety concept for your search.
Use AND to link different concepts. By typing (safe OR “food safety” OR decontamination OR contamination OR disinfect*) AND (beef OR “cattle carcasses”)—you are directing the database to display results containing both concepts.
NOT eliminates all results containing a specific word. Use NOT with caution. The term excluded might be used in a way you have not anticipated, and you will not know because you will not see the missing results.
Learn more about using Boolean operators: Research Basics: Using Boolean Operators to Build a Search (ifis.org)
The search in the matrix above would look like this in a database:
("food safety" OR safety OR decontamination OR contamination OR disinfection) AND (thaw* OR defrost* OR "thawing medium") AND ("sensory quality attributes" OR "sensory perception" OR quality OR aroma OR appearance OR "eating quality" OR juiciness OR mouthfeel OR texture OR "mechanical properties" OR "sensory analysis" OR "rheological properties") AND (beef OR "cattle carcasses")
Thesaurus terms will help you capture variations in words and spellings that researchers might use to refer to the same concept, but you can and should also use other mechanisms utilised by databases to do the same. This is especially important for searches in databases where the thesaurus is not specialised for food science.
Learn how to test if a phrase search or a proximity search is the better choice for your search: Proximity searching, phrase searching, and Boolean AND: 3 techniques to focus your literature search (ifis.org)
Note: Proximity symbols vary from database to database. Some use N plus a number, while others use NEAR, ADJ or W. Always check the database help section to be sure that you are using the right symbols for that database.
Truncating a word mean typing the start of a word, followed by a symbol, usually an asterisk (*). This symbol tells the database to return the letters you have typed followed either by no letters (if appropriate) or letters. It is an easy way to capture a concept that might be expressed with a variety of endings.
Sometimes you need to adjust where you truncate to avoid irrelevant results. See the difference between results for nutri* or nutrit*
Inserting wildcard symbols into words covers spelling variations. In some databases, typing organi?ation would return results with organisation or organization, and flavo#r would bring back results with flavor or flavour.
Note: While the truncation symbol is often *, it can also be $ or !. Wildcard symbols also vary from database to database. $ or ? are sometimes used. Always check the database help section to be sure that you are using the right symbols for that database.
In building a search you can combine all the tools available to you. “Brewer* yeast” , which uses both phrase searching and truncation, will bring back results for brewer yeast, brewer’s yeast and brewers yeast, three variations which are all used in the literature.
BEST PRACTICE RECOMMENDATION: Always check a database's help section to be sure that you are using the correct proximity, truncation or wildcard symbols for that database.
It is good practice to supplement your database searches with handsearching. This is the process of manually looking through the table of contents of journals and conferences to find studies that your database searches missed. A related activity is looking through the reference lists of relevant articles found through database searches. There are three reasons why doing both these things is a good idea:
For handsearching, target journals or conference proceedings that are clearly in the area of your topic and look through tables of contents. Sometimes valuable information within supplements or letters is not indexed within databases.
Academic libraries might subscribe to tools which can speed the process such as Zetoc (which includes conference and journal contents) or Browzine (which only covers journals). You can also see past and current issues’ tables of contents on a journal’s webpage.
Handsearching is a valuable but labour-intensive activity, so think carefully about where to invest your time.
BEST PRACTICE RECOMMENDATION: Ask a colleague, lecturer, or librarian to review your search strategy. This can be very helpful, especially if you are new to a topic. It adds credibility to your literature search and will help ensure that you are running the best search possible.
BEST PRACTICE RECOMMENDATION: Remember to save a detailed record of your searches so that you can run them shortly before you are ready to submit your project to see if any new relevant research has been published since you embarked on your project. A good way to do this is to document:
Keeping all this information will make it easy to see if your search picks up new results when you run it again.
BEST PRACTICE RECOMMENDATION: If you are publishing your research, take note of journals appearing frequently in your search results for an indication of where to publish a research topic for good impact.