Re: [BIONT-DSE] Inclusion versus exclusion criteria

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 01:19:26 UTC