Lesson 3 – Systematic Literature Review Course: Literature Search Terms and PICO

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Choosing the Right Search Terms for Literature Reviews

Effective literature reviews for medical devices require a precise and strategic approach to search terms. By choosing the right terms, you can ensure your search is comprehensive yet focused, leading to high-quality studies that support your device’s claims. Let’s dive into the art and science of selecting the best search terms.

Why Search Terms Matter

Choosing appropriate search terms is essential for a thorough and efficient literature review. The terms must:

• Capture all relevant studies related to your device.
• Demonstrate to reviewers that you performed a global and exhaustive search.
• Prevent you from being overwhelmed with irrelevant abstracts to review.

Breaking Down Research Questions into Searchable Aspects

The process begins with your research question. For example, consider the question: “How effective are wearable ECG monitors in detecting atrial fibrillation compared to traditional Holter monitors?”

Key aspects include:

• Wearable ECG
• Atrial fibrillation
• Holter monitors

Breaking your question into these components helps create focused search queries.

Using Synonyms and Variations for Coverage

Each aspect of your research question should include synonyms and related terms. For example, for “Atrial fibrillation,” you might include:

• Atrial flutter
• AFib
• Cardiac arrhythmia
• Irregular heartbeat

These terms ensure comprehensive coverage and increase the chances of retrieving all relevant literature.

Leveraging the PICO Framework

The PICO framework (Population/Problem, Intervention, Comparison, Outcome) is a powerful tool for structuring your research question and identifying search terms.

1. Population/Problem (P): Who is affected? For example, patients with atrial fibrillation.
2. Intervention (I): What is being studied? E.g., wearable ECG monitors.
3. Comparison (C): What is it compared to? E.g., traditional Holter monitors.
4. Outcome (O): What are the results? E.g., detection accuracy.

This structured approach ensures no critical component is overlooked.

Building Search Blocks with MeSH and Free Text Terms

Search blocks group related terms for each aspect of your research question. Combine:

• MeSH Terms (Medical Subject Headings): Standardized vocabulary in databases like PubMed (e.g., “Atrial Fibrillation” [MeSH]).
• Free Text Terms: Synonyms and variations not covered by MeSH (e.g., “AFib,” “irregular heartbeat”).

Boolean operators (AND, OR, NOT) can further refine your searches:

• AND: Narrows the search by combining terms (e.g., “Atrial Fibrillation” AND “Wearable ECG”).
• OR: Broadens the search by including synonyms (e.g., “Atrial Fibrillation” OR “AFib”).
• NOT: Excludes specific terms (e.g., “Atrial Fibrillation” NOT “Flutter”).

Applying PICO: Practical Examples

1. Surgical Scalpel
   • Population: Surgeons and operating room staff.
   • Intervention: Terms like “surgical scalpel,” “blade,” “surgical knife.”
   • Comparison: Other scalpel brands or materials (e.g., stainless steel).
   • Outcome: Safety and performance metrics like “incision complications” or “cutting efficiency.”
2. Two-Lumen Hemodialysis Catheter
   • Population: Hemodialysis patients.
   • Intervention: “Two-lumen catheter,” “dual-lumen,” specific materials like “polyurethane.”
   • Comparison: Single-lumen catheters.
   • Outcome: Infection rates, thrombosis, flow rates.
3. Dermatology AI Diagnostic Software
   • Population: Patients with skin conditions.
   • Intervention: “AI diagnostic software,” “machine learning.”
   • Comparison: Dermatologist diagnoses or biopsies.
   • Outcome: Diagnostic accuracy, patient satisfaction, time to diagnosis.
4. Suture Anchor
   • Population: Patients undergoing orthopedic surgery.
   • Intervention: “Suture anchor,” “bioabsorbable materials.”
   • Comparison: Different anchor designs or surgical techniques.
   • Outcome: Anchor stability, failure rates, postoperative pain.

FAQs

What are search blocks, MeSH, and free-text terms? Search blocks group related terms. MeSH terms are standardized vocabulary in databases like PubMed, while free-text terms include synonyms and variations for comprehensive searches.

How can I test and refine my search terms? Run preliminary searches to see if your terms yield relevant results. Adjust based on the quality and quantity of the studies retrieved.

Why is term selection critical? Comprehensive and accurate terms ensure thorough coverage of the literature without being overwhelmed by irrelevant results.

Conclusion

Choosing the right search terms is both an art and a science. By breaking down your research question, using frameworks like PICO, and leveraging tools like MeSH, you can ensure your literature review is robust, efficient, and credible. Remember, refining your terms is an iterative process – each step brings you closer to identifying the high-quality studies that matter most.