Rayyan vs Synthesis

Rayyan is a platform for teams carrying out systematic evidence reviews, with workflows intended to be transparent, auditable, and reproducible. Its process spans reference import, collaboration, deduplication, title and abstract screening, full-text screening, data extraction, risk-of-bias assessment, and reporting. ResearchPilot AI Reviewer screens articles against criteria set by the user and gives decisions with reasoning notes. The Analyzer suggests inclusion or exclusion with justification, while the researcher retains final decision-making. ResearchPilot can also extract answers to custom questions from PDFs and metadata, highlight relevant passages, and let users inspect the answers. References are imported from exported files rather than a direct database connection. The API offers programmatic access to reviews, references, decisions, and metadata, plus workflow automation and external integrations. Rayyan is available on Android, iOS, web, and through an API. The Free plan allows three active reviews and two free reviewers; paid options start at $8.33 a month per seat, billed annually. Free mobile access is limited; Essential and higher provide unlimited mobile access.

Synthesis is software for conducting scoping, systematic and regular literature reviews. It organizes references and PDFs, searches abstracts and full-text PDFs by keyword or phrase, and automatically de-duplicates imported references. The support page reports externally validated deduplication sensitivity of 98% and specificity of 99%. Its screening workflow supports primary and secondary reviewers working through abstracts and full text, with kappa scores calculated for both. Analysis tools include AI-assisted topic clustering, word clouds, metadata extraction and charts. Embedded searches cover PubMed, PubMed Central, IEEE, arXiv.org and US Patents; references can also be imported from Ovid, Web of Knowledge, ProQuest and ACM. Synthesis can download many full-text PDFs when open or institutional access is available, and exports references and data as RIS and CSV. The trial allows unlimited projects, but each project can import only 50 references and uses a slower PDF viewer. The maker says orders and downloads are temporarily suspended during development of a new release. Licenses are tied to individual computers; pricing is available on request.