A positive test for a low specific test is even worse in a low
prevalent population as your positive predictive value will be extremely
low.
By the way after my 2nd triathlon I wa breathless and had calf
pain...should I have been started on warfarin....or just accepted that
it was cramp and 1500m swim 40km cycle and 10km run is a long way (for
the non elite athlete like me)
Happy XMAS
Andy Webster
-----Original Message-----
From: Accident and Emergency Academic List
[mailto:[log in to unmask]] On Behalf Of Jel Coward
Sent: 23 December 2002 15:01
To: [log in to unmask]
Subject: Re: D-dimers and the Dyspnoeic Triathlete
In article <001a01c2aa58$314a6bc0$55b33bcb@PaulBailey>, Paul Bailey
<[log in to unmask]> writes
>Regards to all fellow list members at this time of year.
>
>This case beautifully illustrates the situation of the clinician not
>understanding the test he is ordering, and therefore interpreting the
>results incorrectly.
>
>As a lot of you will be aware, D-dimer is a *sensitive* screening test,
not
>a *specific* one..... what this means is that D-dimer is used (by those
who
>believe in it - but that's another story) to exclude the diagnosis of
>DVT/PE, not to make the diagnosis. Sensitivity is said to be around
>95-100%, specificity more like 50%.
I think the following has been written on here before
Spins and snouts (nothing to do with Bickels dizzy (and apostrophally
challenged) pigs!)
SPIN - a SPecific test rules IN
SNOUT a SeNsitive test rules OUT
Cheers and Merry Christmas all :)
--
Jel Coward
The UK Wilderness Emergency Medical Technician and Command Physician
course is
9th-15th November 2003 at Glenmore Lodge, Aviemore, Scotland
http://www.wildmedic.org
http://www.wemsi.org
[log in to unmask]
'There's no such thing as bad weather - just bad clothing"
Anon Norwegian
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