Checklist
Deduplicate before spending attention on screening
Reading the same paper three times is not triangulation.
When it fits
- Results come from several databases, searches or citation rounds.
When to avoid it
- Conference papers, preprints and journal versions can be materially different; do not merge distinct versions blindly.
Checklist
- Stable identifiers are used where available.
- Exact duplicates are merged before screening.
- Retrieval-source metadata is preserved.
- Near-duplicate titles receive manual review.
- Different reports from one underlying study are not automatically treated as independent studies.
Why it matters
Normalize obvious identifiers such as DOI, title and author/year, then merge duplicate records before substantive screening. Preserve links to all retrieval routes so you know which search found the record. Review ambiguous near-duplicates manually instead of deleting them by title similarity alone.
An example
The same AI paper found in Scopus, Google Scholar and forward citations becomes one screening record with three provenance routes.
Check your result
Screening workload counts unique records rather than repeated database entries.
Keep this limit in mind
- Conference papers, preprints and journal versions can be materially different; do not merge distinct versions blindly.
Connected ideas
Use beforeScreen against explicit inclusion criteria, not relevance vibes
Evidence and sources
TARCiS recommends deduplicating supplementary citation-search results before screening.
Deduplication can mistakenly merge distinct records when metadata is poor.
Guidance on terminology, application, and reporting of citation searching: the TARCiS statement · Recommendation 7