Screening is the process of selecting the studies that you will include in your literature review. Ideally, screening should be done by two reviewers and who are blinded - they cannot see each others decisions).The process usually involves two steps:
Select/Reject studies based on title/abstract : it is often easier and faster to start by focusing on your exclusion criteria.
Select/Reject studies based on full text : include studies that match your inclusion criteria.
It is very important to keep track of the number you exclude at each level. At the full-text screening level, it is also common to keep track of your reasons for excluding each paper. The PRISMA Diagram can be used : http://www.prisma-statement.org/
Screening will be based on the inclusion/exclusion criteria that you have set when developing your question. You may introduce bias into the final review if these are not used thoughtfully.
It might be a good idea to go through your inclusion/exclusion criteria with your screening collaborator and agree on a list to be used for screening. You might also want to agree on a list of terms that you would like to see highlighted (green for inclusion terms, red for exclusion) in your screening tools
Rayyan is a free, web-based tool that is highly recommended for screening at both the title/abstract and full-text level. Keep in mind:
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