Publishers and content providers provide article metadata (author, title, subjects, abstract, etc.) to EDS. Each source has slightly different practices around the information they provide. Authors may be cited with their full name by one source, or last name and initial by another. Differences are especially noticeable across different disciplines, where the styles of subject headings can vary dramatically. EDS takes all this disparate content and smooths it out as much as possible without losing important distinctions.
How this affects you: Linked subject searches on an article detail page will find all the other articles that use that style of subject heading, but may exclude relevant material from other sources. Follow links, but be aware that you may be narrowing your focus by more than just the topic.
De-duplication on the fly
Some articles are available from many sources. Exact duplicates are removed from search results as they are displayed. This means that the result count may not be completely accurate until you are looking at the final page of results.