When you upload your references to Rayyan, the tool automatically removes any exact matches from your search results. This ensures that your project only contains unique references, saving you time and effort during the review process. Rayyan lists the duplicates under the Auto-Deduplicated facet and provides a clear breakdown of the results.
To calculate the total number of duplicates removed, Rayyan uses the formula (n-1)*x, where:
n = The number of exact matches
x = The number of duplicates with that number of exact matches.
If Rayyan discovered the following, for instance:
92 citations with 2-exact matches, (2-1)*92 = 92
31 citations with 3-exact matches, (3-1)*31 = 62
18 citations with 4-exact matches, (4-1)*18 = 54
7 citations with 5-exact matches, (5-1)*7 = 28
2 citations with 6-exact matches. (6-1)*2 = 10
To break it down further, Rayyan found and resolved the following number of duplicates based on the number of exact matches:
92 duplicates were removed and 92 were kept for 2 exact matches
62 duplicates were removed and 31 were kept for 3 exact matches
54 duplicates were removed and 18 were kept for 4 exact matches
28 duplicates were removed and 7 were kept for 5 exact matches
10 duplicates were removed and 2 were kept for 6 exact matches