Thomas Beale wrote: > Tim Churches wrote: >> >>> Tim, if the accuracy_is_percent attribute was upgraded to a coded >>> value, could you suggest a set of meanings that would cover all the >>> epi/PH needs? >>> >> >> You'll have to tell me what that would involve. A single coded value? >> Upper and lower limits? Confidence level. Type of limit? >> > well, essentially what you are proposing
Not proposing anything, I'm just asking the question "Have you thought about this?" > would require (let's not get > too pure about how I use the word "accuracy" here for the moment): > - lower accuracy limit: Real > - upper accuracy limit: Real > - accuracy limit type: coded term > - confidence level (or this could be part of the previous coded > attribute, since only a small number of confidence bands are used in > practice aren't they?) > > Now, what we currently have is a set of general purpose quantity classes > designed to enabled recording of any quantitative data we have come > across so far. Between various MDs such as Sam, Vince and others, I > think we have pathology covered from a practical point of view (well, we > do once we get this <, >, etc thing sorted). Just curious: have you had much input from pathologists, microbiologists and lab scientists? The more one talks to such people, the more one discovers about the uncertainties inherent in certain assay techniques, and the differences in the scalar (and qualitative or Boolean) results produced by different assay kits and different labs. Oh, there's another form of uncertainty which typically is of relevance to Boolean/dichotomous results (positive/negative, detected/not detected etc) and that is the sensitivity and specificity of the test, or the related quantities PPV (positive predictive value) and NPV. (Note to computer scientists: "specificity" and "sensitivity" are cognate with "precision" and "recall".) > The real question is: what is the type & origin of data that need to > represented in the more sophisticated way that we are now suggesting? Is > it a different category of data? Should be leave the current DV_QUANTITY > as is and add a new subtype? Or is it that we should consider a quantity > with a 95% T-distribution confidence interval as a pretty normal thing? > Should we then start considering the "simple" idea of a symmetric > accuracy range (+/- xxx) as really just one specific type of a > confidence interval (it might translate to something like 98% on a > normal curve). In other words, should we generalise he "accuracy" notion > into a "confidence interval" notion? I think that a one or two day workshop with a range of pathologists, microbiologists, lab scientists, epidemiologists and statisticians (and some clinicians and computer scientists, of course) would suffice to come up with sensible answer to your question. I'd be happy to participate and to suggest other participants. First half day would need to be spent bringing everyone up to speed on openEHR so they understand the nature of the question(s) to be addressed (and a good means of spreading the openEHR gospel while you're at it...). Might be possible to hold a cyber-workshop instead, via email or real-time conferencing. The former would be much slower, of course. Tim C
