The most common reason for abstracts to be missing in Covidence is because they are missing in the import file. We recommend checking that the abstracts are present in the file before it is imported to Covidence, and also checking the settings used to download this file from the search.
You can undo an import in Covidence if you have not yet begun screening. If screening is already underway, it will not be possible to undo the import. Instead, you can contact us to request a re-set of your review.