Author Archives: wolandscat

About wolandscat

I work on semantic architectures for interoperability of information systems. Much of my time is spent studying biomedical knowledge using methods from philosophy, particularly ontology and epistemology.

Directions in clinical guideline programming – CHA2DS2-VASc

The above shows a typical web form calculator for the CHA2DS2-VASc score, used for estimating the risk of stroke in patients with non-rheumatic atrial fibrillation (AF), primarily for the purpose of deciding the use of anti-coagulant therapy [Wikipedia]. How would such … Continue reading

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Design-by-Contract (DbC) v Test-Driven Design (TDD)

Another bit of software engineering knowledge from my archive relates to two well-known formal quality methods used in software development. This is from a presentation made at ETH Zurich in 2010.

Posted in Computing | 5 Comments

Software – from Development to Use and Ownership

Here’s an infographic (alright, it’s just a diagram) I created over a decade ago, randomly extracted from the archives. I think it’s almost self-explanatory. Here’s a few more slides using this. I wouldn’t adjust too much today, but note that … Continue reading

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Nominalism versus Ontology

Most nominalist arguments are straightforwardly wrong, but not for the usual reasons that universals and/or abstracta are said by realists to exist, but for the opposite reason: types and abstracta are ‘just there’, even if they don’t ‘exist’, in the sense of being spatio-temporally concretised. The real problem is that we misuse the word ‘exists’ at least half the time in philosophy. Continue reading

Posted in Philosophy | Tagged | 2 Comments

Aide Memoire for Computable Domain Models

Sometimes a graphic is worth more than words. This is an attempt to capture all the salient features of multi-level modelling, the openEHR way. See the openEHR primer for the story. Although this is ‘our way’ of doing it, I … Continue reading

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Clinical Decision Logic Fun

How close can we get to making a clinical decision logic language look like the published guidelines which it is used to encode? Below is an openEHR Decision Logic Module (DLM) example, in the current form of the openEHR Decision … Continue reading

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Towards a standard analysis of computable guidelines, clinical workflow, decision support and … the curly braces problem

Why don’t we have widespread clinical decision support (CDS), computable guidelines, clinical workflow (plans), and why don’t the pieces we do have talk to the health record? The first time I heard such challenges framed was around 2000, and even … Continue reading

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FHIR Fixes – the choice construct part I

I have posted before on the FHIR ‘choice’ construct, particularly here, where I have explained the problems of the choice construct (essentially: it’s an ad hoc constraint construct that subverts the type system, and doesn’t belong in typed formalisms; none … Continue reading

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FHIR fixes: why a type hierarchy would help

One of the principal reasons for why I and others are proposing (some) type hierarchy in the FHIR Admin resources is as follows (my earlier post on this). Working Groups (i.e. committees) building Resources are currently in the situation of … Continue reading

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FHIR Fixes – the Observation.value problem

As described in some detail in this earlier post on the FHIR formalism, a number of FHIR Resources contain ‘choice’ attributes of the form attribute[x], such as the one shown above in Observation. These are mapped in the FHIR UML … Continue reading

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