Angus

I tried a brief test using Medline (MEDL) and Embase (EMED) and searched
for the journal Epilepsia, knowing that this journal is indexed by both
databases, and combining with the author Smith (not very inspired
searching I know!).

I retrieved nine references of which three appeared twice in the results.
After de-duplicating, the three duplicated items were correctly removed
leaving me with six unique items. So de-duping seems to have worked on
this occasion.

However, I can report that the de-duplicating feature hasn't always worked
for me. A recent cross-search of two databases produced a large set of
results which, after de-duplicating, I imported into Reference Manager. A
good number of additional duplicates were identified by that software. It
is worrying that the process doesn't seem to be consistent and I would
welcome more information about how it works and how reliable we can
consider it to be.

It's also interesting to note that in my little test today, the MEDL item
was removed each time rather than the EMED one. It would be interesting to
know how this decision is made by the software.

Regards,
Kate

Kate Brunskill
Deputy Librarian - Rockefeller Medical Library
UCL Institute of Neurology & National Hospital for Neurology and Neurosurgery
[P] 020 7829 8709
[F] 020 7278 1371
[E] [log in to unmask]


> APOLOGIES FOR CROSS POSTING
>
> Hi everyone,
>
> Can anyone out there confirm for me that the remove duplicates function
> on Dialog is not working properly, or tell me if I have misunderstood
> it's purpose?
>
> Currently when I search across two or more databases I remove duplicates
> in order to deduplicate the results -  leaving me with a complete set of
> unique records. Crucially though, this unique set should still contain
> one (the original, if you like) entry for each paper found. What I'm
> finding though, is that remove duplicates removes every instance of that
> record from the deduplicated set including the original one. Thus any
> paper that has been indexed by more than one database is completely
> removed from my deduplicated set. Obviously this means that major
> journals indexed by both Medline and Embase get the chop.
>
> I'd be grateful for any help or explanations offered.
>
> Regards,
> Angus.
>
>
> Angus Leitch, Electronic Development Librarian
> Health Library, Clinical Education Centre,
> University Hospital of North Staffordshire NHS Trust,
> Newcastle Road, Stoke on Trent. ST4 6QG.
>
> Tel: 01782 556581/ 01782 556565
> Fax: 01782 556582
> Email: [log in to unmask]
> www.keele.ac.uk/depts/li/hl/
>