Currently, Covidence does not allow for direct import from databases, so you'll be using the RIS files that you exported from your database searches.
To Import your RIS Files:
Covidence has an automatic de-duplication function built in that checks each import for duplicates against previous imports. It isn't perfect, but does a pretty good job with most databases.
Reviewing Duplicates Removed:
You should always review the duplicates the system found to ensure there weren't any incorrectly identified.
Noting Duplicates While Screening:
The easiest way to ensure you find missed duplicates while screening, is to review the screening lists using Title sorting.