What the protocol controls
The protocol is the blueprint for the review. It reduces ad hoc decisions and provides the foundation for the methodology section.
Specify in advance
- Background, purpose, objectives, and research questions.
- Databases, search fields, years, languages, and publication types.
- Inclusion and exclusion criteria.
- Deduplication and screening procedures.
- Quality assessment instrument and threshold.
- Data extraction fields and synthesis method.
- Reviewer roles, conflict resolution, and record keeping.
Protocol rule
If the protocol changes, record what changed, when it changed, and why. Do not silently modify criteria after screening begins.
Quality check
- Another reviewer could repeat the planned process.
- Criteria are operational and unambiguous.
- Every RQ is linked to extraction and synthesis.
- Roles and disagreement procedures are defined.