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ELC6002/ELC6012 - Thesis Writing for Research Students

Course Guide for ELC6002/ELC6012 Students

Now we are ready to dive into a more sophisticated search in article databases, aiming to get more relevant studies effectively. Let's first take a look at how to:

  • Build an effective search statement using Advanced Search
  • Explore similar articles through citation chaining

Build an Effective Searching Statement

Advanced Search allows you to build a more structured search statement. This helps you find relevant results more efficiently.  Many article databases, such as Web of Science or Scopus, offer the Advanced Search function.

With the multiple lines structure, you can type in keywords representing different concepts in separate lines and specify the search field for each line.

Advanced Search
  Enter a search term
Enter a search term
Enter a search term
  Add a New Line   Search

You can also apply searching techniques, e.g. combine your search terms with Boolean operators (AND, OR, NOT) to make your search more precise.


Steps to Build a Search Statement in an Article Database

In this example, we will use Web of Science to demonstrate the searching process. Web of Science is a multidisciplinary database covering over 20k peer-reviewed journals. You can apply the techniques to other article databases in your subject area as well.

From the preliminary search, you may have identified a few keywords and related terms for your research topic. Pick 2-4 core keywords that represent different concepts. The keywords are usually nouns or noun phrases.

Assume our research topic is: "The impact of COVID on mental health of University students in Hong Kong".

The keywords picked could be:  COVID, mental health, University students, Hong Kong

Go to Web of Science database.

Add in more rows to include keywords representing different concents, and use AND to combine the keywords so that the search results will include all these keywords.

To make your search more precise, you may:

  • Use quotation marks " " to enclose the phrase to search the terms as a phrase. This is known as a phrase search.
  • Limit your search to specific search field, e.g. Topic (includes Title, Keywords, Abstract), or Title, based on your search results. 

In our case: 

Advanced Search
  Topic COVID
AND Topic "mental health"
AND Topic university students
AND Topic Hong Kong
  Add Row   Search

When you run this search in Web of Science, you will notice there are very few results. Here we can expand our search by adding alternative keywords. 

Use OR to combine the alternative keywords (or synonyms) so that articles containing at least one of the keywords will be included in the results.

You may also:

  • Use truncations * to include variants of a word, e.g. transmit* searches transmit, transmittion, transmitted, etc.
  • Use parentheses ( ) to enclose the phrase to specify the order of operators (terms within parentheses will be executed first). This is usually used when you compose the search query in one line with multiple operators.  

In our case: 

Advanced Search
  Topic COVID OR coronavirus OR pandemic OR lockdown
AND Topic "mental health" OR depression OR anxiety
AND Topic university OR college OR "higher education"
AND Topic student* OR "young adult*" OR "young people"
AND Title "Hong Kong" OR China OR Chinese OR Asia
  Add Row   Search

Try this search again and see the difference. Note that we changed the last search field to "Title" so that only articles with the keywords in their title will be retrieved. This again makes our search more specific.

The last step is to refine your search results using filters, e.g.

  • Publication year range
  • Subject category / Research areas
  • Document type (e.g. articles, review articles, conference papers)
  • and more

You can find similar filter options in many other article databases. 

Don't target for a perfect search statement on your first try! Between the steps 2 and 3, there could be many trial searches involved until you retrieve a manageable number of relevant results. You may discover new keywords or even refine your research topic during the searching process.

Read More Search Tips to learn more about Boolean Operators, Truncation, and Phrase search.

Explore Similar Articles

Once you have identified some key studies, you will probably want to find more similar studies. You can use citation chaining (also referred as Backward and Forward searching) to help you achieve this.

The diagram below illustrates how this works when you are trying to find similar articles of your "perfect" article ("A").

citation chaining

Research is constantly building upon others’ ideas and key findings are linked between papers through citations made by authors.

By tracing the development of your “perfect” article across time, you would be able to find articles ("B") that had an impact on this article and also the articles ("C") it influenced thereafter.

Where to Find Citing Articles?

It is easy to do backward searching - we just need to check the article's reference list. But how do we do forward searching and find the citing articles?

Many article databases offer citation information for the articles covered in the database. These databases are referred as citation databases. You can locate an article's citing articles by tracking terms such as "Cited by", "Times Cited", "Citing articles" or "Citing references". 

Here are a few examples from commonly used citation databases:

Citation Chain Web of Science

View this sample article on Web of Science

  • A - the "perfect" article found on Web of Science
  • B - find A's references, the articles that had an impact on A
  • C - find A's citing articles, the articles influenced by A
  • You can also find some related articles through "You may also like...".
  • For some articles, you can view the article's references in the context through "Enriched Cited References" feature, i.e. to view references by their location in the paper. References appearing in Results or Discussion may be more relevant to your topic.

View this sample article on Scopus

  • A - the "perfect" article found on Scopus
  • B - find A's references, the articles that had an impact on A
  • C - find A's citing articles, the articles influenced by A
  • You can also find some related articles under "Related documents".

Citation Chain PubMed

View this sample article on PubMed

  • A - the "perfect" article found on PubMed
  • B - find A's references, the articles that had an impact on A
  • C - find A's citing articles, the articles influenced by A
  • You can also find some related articles under "Similar articles".

Citation Chain Google Scholar

View this sample article on Google Scholar

  • A - the "perfect" article found on Google Scholar
  • C - find A's citing articles, the articles influenced by A
  • You can also find some related articles through "Related articles".

Other citation databases

Some free platforms that offer citation info