EBSCOhost Integrated Search (EHIS) retrieves a relevancy ranked result list from each target source. It takes the top 30+ results from each and merges them into a single result list. EHIS then applies its own relevancy ranking to this merged list to get the sorted records you see on the result list.
De-duplication has two primary logics, one for journal articles and one for books/catalog records.
Journals are deduped based on: Date Published, Journal Name, Title, ISSN, Full Text. EHIS strives to display the highest quality record, so for example, if one record has full text, that record will be displayed.
Books and catalog records are deduped based on: Date Published, Volume, Issue, Start Page, Title, ISBN, Physical Description, Publisher, Holding Location, Full Text. EHIS will prevent unnecessary de-duplication of records. For example, if three records have the same title, but different ISBN’s, EHIS will show all three records and not de-duplicate.