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Evidence Based Literature Searching

🛠️ Basic Search Tips

  • 🔍 Search each concept separately and build your search one step at a time.
  • 🧠 Think of synonyms for each PICO element to expand your results.
  • 📚 Choose a relevant database (e.g., CINAHL for nursing literature).
  • 🌐 Try multiple databases - don’t rely on just one.
  • 🎓 Check out our Database Searching Tutorials for platform-specific tips.

🔗 Boolean Operators

Use Boolean operators to control the scope of your search:

        Operator      Effect Example
        AND Narrows your search asthma AND children
        OR Broadens your search      asthma OR wheezing     
        NOT Excludes terms asthma NOT adult

 

🧩 Word Choices & Search Strategy

✅ Use Controlled Vocabulary

  • MeSH (Medical Subject Headings) in PubMed
  • Subject Headings in other databases
  • Helps retrieve articles indexed under standardized terms

✅ Use Natural Language (Keywords)

  • Use your own words or those from article titles and abstracts
  • Combine with controlled vocabulary for a broader, more effective search

💡 Pro Tip: Don’t rely only on controlled vocabulary—some articles may not be indexed yet

💡 Pro Tip: Find a few relevant articles and check the Assigned MeSH terms or subject headings, Keywords listed by authors, and terms in the title and abstract

🎛️ Filters & Limits

Use filters to narrow large search results:

  • 📅 Publication date
  • 🧪 Study type
  • 🌍 Language (e.g., English)

⚠️ Pro Tip: Use filters with caution—they can unintentionally exclude valuable articles.

🧪 Troubleshooting a Search Strategy

If your search isn’t returning relevant articles, try these strategies to refine and improve it:

🔍 Revisit Your Question

  • Is your topic too specific or too broad?
  • Consider reframing or simplifying your question.

🧠 Rethink Your Search Terms

  • Explore controlled vocabulary (e.g., MeSH terms).
  • Look for synonyms in titles and abstracts of relevant articles.
  • Add new terms based on what you find in well-targeted articles.

📚 Reevaluate Your Database Choices

  • Are you using the right database for your topic?
  • Try another database that covers your subject area more thoroughly.

🤝 Ask for Help

  • Consult a colleague or librarian for fresh ideas.
  • Different perspectives can uncover new terms or resources.

❗ Consider the Possibility: The Evidence Might Not Exist

In the age of technology, it’s easy to assume everything has been studied—but that’s not always the case.

Reasons evidence may be missing:

  • Proprietary or unpublished research
  • Underfunded topics
  • Positive publication bias
  • Not indexed in the databases you're using

🔄 What to Do If Evidence Is Missing

If you’ve exhausted your options and still can’t find relevant literature:

  • Be open to revising your question.
  • Consider exploring related topics or alternative approaches.