- From: Chintan Patel <chintan.patel@dbmi.columbia.edu>
- Date: Tue, 11 Sep 2007 21:11:27 -0400
- To: Alan Ruttenberg <alanruttenberg@gmail.com>
- Cc: Vipul Kashyap <VKASHYAP1@PARTNERS.ORG>, "Andersson, Bo H" <Bo.H.Andersson@astrazeneca.com>, Landen Bain <lbain@topsailtech.com>, Rachel Richesson <Rachel.Richesson@epi.usf.edu>, public-semweb-lifesci hcls <public-semweb-lifesci@w3.org>, public-hcls-dse@w3.org, Stanley Huff <Stan.Huff@intermountainmail.org>, Yan Heras <Yan.Heras@intermountainmail.org>, "Oniki, Tom (GE Healthcare, consultant)" <Tom.Oniki@ge.com>, Joey Coyle <joey@xcoyle.com>, "Bron W. Kisler" <bkisler@earthlink.net>, Ida Sim <sim@medicine.ucsf.edu>
Hi Alan, Regarding negation of exclusion criteria, it is interesting that you mention open versus closed world reasoning. We have found that depending on the underlying clinical data being queried, we might need to choose between open and closed world reasoning. For example, in pharmacy data, if the patient record does not mention a drug, we can be reasonably sure that the patient is not on that drug -- a case for closed world reasoning, whereas for other datasets such as lab or radiology, often things are explicitly asserted to be negative if not present, for example, negative MRSA results, hence requiring an open world reasoning approach. We also found that implementing exclusion criteria as queries is simply not a matter of OR-ed negations, atleast within the Semantic Web framework. In description logics, generally the ABox queries are negated and then added to the knowledge base to find the matching individuals (by contradiction), so if our query itself is negated, internally the reasoner will negate it again and hence we ll not find any matching results. So the solution we used was to perform a set difference between the patients matching the inclusion and exclusion criteria. my 2 cents. Thanks, Chintan --- PhD Candidate Biomedical Informatics Columbia University On Sep 11, 2007, at 12:53 PM, Alan Ruttenberg wrote: > > Something that I remain confused about is why there are two > categories of criteria, when, on the face of it, the negation of an > exclusion criterion is an inclusion criterion. > > So I'm wondering, is there something between the lines? Is there > something other than the negation? Perhaps kind of criteria, or > lesser necessity, or derivation from different sources? Open versus > closed world? Otherwise, from a technical point of view can we just > consider these the the same sort of thing, with a flag indicating > how they should be shown in a hypothetical user interface? > > -Alan >
Received on Wednesday, 12 September 2007 01:11:44 UTC