This is an excellent and crucial step for any systematic review! Peer review of your search strategy using the PRESS (Peer Review of Electronic Search Strategies) checklist significantly enhances the quality, comprehensiveness, and reproducibility of your review.

Here's a comprehensive guide to help you navigate this process:

Guide to Peer-Reviewing Your Systematic Review Search Strategy Using PRESS

The PRESS checklist is designed to improve the quality of systematic review search strategies. It provides a structured approach for an experienced information specialist or librarian to review your planned search.

Goal: To ensure your search strategy is comprehensive, accurate, reproducible, and aligns with your review's objectives before you invest time and resources in screening results.

Phase 1: Preparation (By You, the Searcher/Review Team)

Before you even approach a peer reviewer, you need to have your materials in order. The more complete and clear your documentation, the more effective the peer review will be.

• Develop Your Research Question (PICO/PEO):


• Clearly define your Population (P), Intervention (I), Comparison (C), Outcome (O) – or Population (P), Exposure (E), Outcome (O) for qualitative/observational reviews.


• This is the foundation of your search.


• Draft Your Review Protocol:


• Though not the focus of the search review, having a draft protocol (or at least key sections like inclusion/exclusion criteria) provides essential context for the reviewer.


• Mention specific eligibility criteria (e.g., date limits, language limits, study designs).


• Identify Key Concepts for Each PICO Element:


• Brainstorm all possible terms, synonyms, related concepts, acronyms, and alternative spellings for each element of your PICO.


• Develop a Preliminary Search Strategy for Each Database:


• Start with one primary database (e.g., MEDLINE/PubMed, Embase) and develop a robust strategy there first. This strategy will then be adapted for other databases.


• Use appropriate controlled vocabulary (e.g., MeSH for PubMed/MEDLINE, Emtree for Embase) AND free-text terms (keywords).


• Combine terms using Boolean operators (AND, OR, NOT).


• **Utilize truncation (*), wildcards (?), proximity operators (adj, N), and field codes (e.g., [tiab] for title/abstract).**


• Document EVERYTHING: The exact syntax, database platform (e.g., Ovid MEDLINE, EBSCO CINAHL, Web of Science Core Collection), date of strategy development.


• Compile a List of "Gold Standard" or Benchmark Papers:


• Identify 3-5 highly relevant, seminal papers that you know must be retrieved by your search. These will be used to test the recall of your strategy.


• Provide their full citations (author, title, journal, year).


• Organize Your Materials:


• Create a single document or folder that contains:


• Your PICO/PEO question.


• Brief overview of inclusion/exclusion criteria.


• Your preliminary search strategies for each planned database (ideally starting with the most developed one).


• Your list of "gold standard" papers.


• Any rationale for specific term choices or search syntax decisions.

Phase 2: Selecting a Peer Reviewer

The quality of the review depends on the reviewer's expertise.

• Identify a Qualified Reviewer:


• An experienced information specialist or librarian with expertise in systematic review methodology and searching.


• Someone who is not part of your immediate review team to ensure an objective perspective.


• Ideally, someone who uses the databases you plan to search regularly.


• Where to find them: University librarians, hospital librarians, professional library associations, or by networking with other systematic review teams.


• Initiate Contact:


• Clearly explain your request, the timeline, and the scope of the review (i.e., focus on the search strategy using PRESS).


• Be respectful of their time and offer appropriate acknowledgment in your final review.

Phase 3: The Peer Review Process (Using the PRESS Checklist)

Once you've identified a reviewer and prepared your materials, share them. The reviewer will use the PRESS checklist as their guide.

Understanding the PRESS Checklist Categories (and what the reviewer will be looking for, and you should anticipate):

The PRESS 2015 Guideline consists of 6 main categories with detailed items for each. While the reviewer will fill out the checklist, you, as the searcher, should understand what each category addresses.

PRESS Checklist Category 1: Documentation (D)

• What it addresses: The clarity, completeness, and reproducibility of the documented search strategy.


• Reviewer will check for:


• D1 - Database Name/Platform: Are the specific names of the databases and search platforms (e.g., Ovid MEDLINE vs. PubMed) clearly stated?


• D2 - Date: Is the date the search strategy was developed/run included?


• D3 - Searcher Name: Is the name of the person who created the strategy included? (Less critical for peer review, but good practice).


• D4 - Full Search Strategy: Is the entire, line-by-line strategy provided for each database?


• D5 - Translation: If the strategy was translated across databases, is the original (e.g., MEDLINE) strategy clearly marked?


• D6 - Comments/Notes: Are there any notes explaining rationale, specific decisions, or limitations?


• Your takeaway: Ensure your search strategy document is a standalone, clear, and complete record for each database.

PRESS Checklist Category 2: Concepts (C)

• What it addresses: Whether all PICO/PEO elements are represented and adequately covered with appropriate terms.


• Reviewer will check for:


• C1 - Concepts Included: Are all PICO/PEO concepts represented in the search strategy?


• C2 - Controlled Vocabulary: Has relevant controlled vocabulary (e.g., MeSH, Emtree, CINAHL headings) been used appropriately for each concept?


• C3 - Keywords/Free-text Terms: Have sufficient keywords/free-text terms been used for each concept, including synonyms, acronyms, and relevant phrases?


• C4 - Truncation/Wildcards: Are truncation and wildcards used effectively to capture variations (e.g., child* for child, children, childhood)? Are they used too broadly?


• C5 - Spelling Variations: Have common spelling variations (e.g., British vs. American English) been considered?


• C6 - Proximity Operators: Are proximity operators (e.g., ADJ, NEAR) used where appropriate to increase precision without losing recall?


• C7 - Exclusion Terms: Are there any terms that should be excluded using NOT to improve precision without missing relevant articles? (Use NOT cautiously).


• Your takeaway: Critically evaluate if you've cast a wide enough net for each concept, balancing recall and precision.

PRESS Checklist Category 3: Logic (L)

• What it addresses: The correct application of Boolean operators, nesting, and field codes.


• Reviewer will check for:


• L1 - Boolean Operators: Are AND/OR/NOT operators used correctly to combine concepts and terms?


• L2 - Nesting/Parentheses: Is nesting used correctly to group terms and ensure proper order of operations? (e.g., (term A OR term B) AND (term C OR term D)).


• L3 - Field Codes: Are appropriate field codes (e.g., [tiab], [mh], [pt]) used for each term or line?


• L4 - Syntax: Is the overall syntax correct for the specific database and platform being used? (e.g., PubMed syntax differs from Ovid).


• L5 - Limits/Filters: Are any limits or filters (e.g., publication date, language, study type) applied appropriately and documented? Are they too restrictive?


• Your takeaway: Precision is key here. One misplaced parenthesis or incorrect field code can significantly alter your results.

PRESS Checklist Category 4: Appropriateness (A)

• What it addresses: The suitability of the overall strategy for the review question and database choice.


• Reviewer will check for:


• A1 - Database Selection: Are the chosen databases appropriate and sufficient for the research question? (e.g., MEDLINE for health, PsycINFO for psychology, Web of Science for broader citations).


• A2 - "Gold Standard" Papers: Does the strategy successfully retrieve the "gold standard" papers you provided? If not, why? This is a critical check.


• A3 - Scope: Is the search too broad (retrieving too much irrelevant material) or too narrow (missing relevant articles)?


• A4 - Other Sources: Are other search methods (e.g., hand-searching, grey literature, citation chaining) considered if appropriate for the review?


• Your takeaway: This category validates the effectiveness of your strategy. The gold standard papers are your litmus test.

PRESS Checklist Category 5: Clarity of Presentation (P)

• What it addresses: How easy it is for others (and your future self!) to understand and interpret the strategy.


• Reviewer will check for:


• P1 - Readability: Is the strategy well-formatted and easy to read? (e.g., consistent indentation, clear line numbering).


• P2 - Logical Grouping: Are related terms grouped logically?


• P3 - Comments: Are there sufficient comments to explain complex parts of the strategy?


• Your takeaway: A well-presented strategy is easier to review, replicate, and report.

PRESS Checklist Category 6: Overall Assessment (O)

• What it addresses: The reviewer's overall impression and any final recommendations.


• Reviewer will check for:


• O1 - General Impression: What is the reviewer's overall assessment of the search strategy (e.g., excellent, good, needs major revisions)?


• O2 - Major Recommendations: Any critical issues that must be addressed.


• O3 - Minor Recommendations: Suggestions for improvement, but not critical flaws.


• O4 - Confidence: How confident is the reviewer that the strategy will retrieve relevant articles?


• Your takeaway: This is the summary feedback. Be open to all recommendations.

Phase 4: Responding to Feedback (By You)

• Receive and Review Feedback:


• Read through the completed PRESS checklist and any additional comments from the reviewer carefully.


• Don't take criticism personally; it's about improving the review.


• Prioritize Changes:


• Address critical issues (e.g., missing PICO concepts, incorrect Boolean logic that drastically alters results) first.


• Then, consider minor suggestions that will improve precision or recall.


• Implement Revisions:


• Make the necessary changes to your search strategy in each database.


• Re-run your "gold standard" papers test if significant changes were made.


• Document Your Changes:


• Keep a clear record of all changes made in response to the peer review. This is important for transparency and for your final reporting. You might create a table listing "Reviewer Suggestion" and "Your Action/Response."


• Communicate with the Reviewer (Optional but Recommended):


• If there were complex issues or if you have questions about their feedback, follow up with the reviewer.


• Thank them for their time and valuable input.

Phase 5: Finalization & Documentation

• Finalize Strategies: Once satisfied with all revisions, your search strategies are ready to be executed.


• Execute Searches: Run your finalized strategies in each planned database.


• Document Results: Record the number of hits from each database and the date each search was run.


• Report in Your Review: In your systematic review, be sure to:


• Describe the peer review process.


• Mention that the PRESS checklist was used.


• Acknowledge the information specialist/librarian who conducted the review.


• Include your final, complete search strategies (often in an appendix or supplementary material).

By following this structured approach, you will significantly enhance the quality and robustness of your systematic review's search strategy, a foundational element for a successful review. Good luck!