Posted by Larry Hoover on August 14, 2007, at 12:05:55
In reply to Re: Are there statistics on misdiagnoses? » Larry Hoover, posted by Squiggles on August 14, 2007, at 11:14:15
> > You might be interested in this article:
> > http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=1313675&blobtype=pdf
> >
> > Lar
>
> Thanks for replying to my question Larry; can you say something about "sensitivity" and "foreknowledge" in assessment of criteria-- i am not familiar with these concepts.
>
> tx
>
> SquigglesFrom: http://www.poems.msu.edu/EBM/Diagnosis/SensSpec.htm
"sensitivity = probability of a positive test among patients with disease"
"rule of thumb is the acronym "SnNOut", which is taken from the phrase: 'Sensitive test when Negative rules Out disease'."So, the in context of this article, the presence of actual cases of depression among the group "chronic nervous function complaints" indicates that the general practitioners applied foreknowledge in excluding them from the depressed group, reducing the sensitivity of the criteria making up the DSM-IV category of major depression. I.e. these were "false negatives", depressed individuals with other chronic health complaints.
The issue of foreknowledge is well-defined in the first paragraph of the Introduction, IMHO.
The net impression is that GPs may under-diagnose depression a little more than they over-diagnose it; 7 false negatives vs. 5 false positives (difference non-significant). Nonetheless, they're pretty good at diagnosing it, overall.
There are limitations introduced by the different diagnostic definitions used (ICHPPC-2 vs. DSM-IV), but I can find problems with any study. ;-)
Lar
poster:Larry Hoover
thread:776178
URL: http://www.dr-bob.org/babble/20070808/msgs/776210.html