Keep in mind when writing the “Search Methods” section:
Objectives of the methods section:
- Transparency
- Describe the measures taken to minimize bias
- Explain the steps used to ensure comprehensive coverage of the evidence
- Reproducibility
- Provide sufficient detail to allow others to reproduce the search strategy
Writing tips:
Consider your audience: Who is likely to read the methods section? You may need to explain elements that seem obvious. Write a detailed account of what was done.
Key points from the PRISMA 2020 Checklist regarding the search strategy
Information sources
- Date of last search: Report the date when the search was last run.
- Databases and websites consulted: List the full name of each database, website (with links), and registry searched.
- Platforms and coverage periods: Specify the platforms used to access the databases and the time spans covered.
- Handsearching: Describe the journals or conferences manually screened.
- Citation searching: Indicate whether citation searching was conducted.
- Reference list checking: Explain how reference lists were selected and analyzed.
- Author contact strategy: Describe the method used to contact authors, if applicable.
Search strategy
- Search approaches: Line-by-line strategies for complex searches, or sequence of terms for simpler searches.
- Filters and limits applied: Describe any limits, filters, or search hedges used, with a clear justification (and cite sources if applicable).
- Tools used: Mention tools employed to automate parts of the process.
- Validation of the search strategy: Indicate the steps taken to validate the strategy used.
- Peer review process: Describe any methods used to submit the strategy for peer review.
- Conceptual framework: Explain the framework used to structure the search (e.g., PICO or another model).
Discussion
- Limitations of available data:
- Some relevant studies may be missing (due to strict criteria, languages, or timeframes).
- The quality and completeness of data in included studies may vary.
- Access to unpublished studies or grey literature may be limited.
- Limitations of the review process:
- Search strategies may be too restrictive or poorly adapted.
- Potential biases in study selection or data extraction.
- Time, resource, or tool constraints that may reduce the depth of analysis.
- Variability among reviewers that could introduce subjectivity.
In the context of a systematic review, it is often recommended to include a detailed appendix documenting the search strategy to ensure transparency and reproducibility. Elements to include:
- Search summary:
- Use a summary table or list.
- Provide the name of each database, the platform used, coverage period, search date, and number of results retrieved.
- Search updates:
- Report any information about updated or repeated searches during the project.
- Exact search details:
- Include the exact search strings as executed, including any limits applied.
- Attribution and methodology:
- Acknowledge any search filters, strategies, or methodological frameworks used to guide or refine the search.
- Grey literature:
- Document details of searches conducted in non-traditional sources (grey literature), including methods and tools used.
