Overlap, Duplicates Relevant and Unique Hits
Unique Hits
Unique hits are defined as "articles found on one database only" (McGinn et al. 2016, p.271) these are
interesting as they have not appeared on any other data bases
Overlap
• Hood and Wilson (2003) discuss overlap and is described in McFadden et al. (2012) and McGinn et
al. (2016) as fuzzy set theory. In this search there was overlap in the databases Barroso et al. (2003,
p.168) make this point that "overlap or duplicate search results may be attributed to inclusion
practices of the various indexing and abstracting database producers".
• In this search example many of the databases are grouped in the ProQuest collection that is ASSIA,
ERIC, SCOPUS, IBSS and SSA databases and U-search, British Education Index and CINAHL in
EBSCOhost. As Hood and Wilson (2003) highlight there are also duplicates appearing within some
database searches "overlap or duplication within a database" (Hood and Wilson,2003 p.1093) which
had to be removed manually or with a filter option.