What is a ‘clinical statement’?

In the CIMI forum, a debate is raging about this question. It might partly be my fault for daring to question some things in the reference model, but having done that, various participants are indeed arguing. So that’s a vindication 🙂

socrates

These kinds of terms are bandied about all the time in health, but it appears that few people agree on what they mean. And that means we can’t have meaningful conversations. We need some common definitions in CIMI, because otherwise the names of things in our models don’t have a common meaning. And if we don’t know what anything means, we are probably mad. Well, you probably are. I’m not, obviously.

So what is a ‘clinical statement’?

I’m not going to go into a long theoretical argument, I’m just going to pin up some definitions and wait for the flak… I’ll do it from the point of view of addressing some concrete problems in the CIMI space (but common to any multi-level situation):

  • what is an ‘Entry’ (i.e. the class in the information model on which the CIMi archetypes are based)?
  • can an Entry contain other Entries?
  • does an Entry = a clinical statement?
  • can a clinical statement contain more than one data item (defined by 1 archetype node)?
  • what does an archetype node correspond to anyway?

So here’s my take:

  • CIMI metaphysics:
    • fact (factum) – a state of an object or event in a process in the real world (independent of observation)
    • statement – something a human (or maybe a machine) says and/or records that relates to a common context
  • CIMI epistemology – aka types of statement:
    • observation – a record of one or more facts obtained by observation
      • e.g. a blood pressure measurement includes systolic BP, diastolic BP, patient position, exertion
    • opinion – an assessment or evaluation of some facts against a knowledge base;
      • e.g. diagnosis, prognosis, a goal
    • directive / instruction – a statement of an order to be carried out for the subject of care
      • e.g. a prescription; an order for a lab test;
    • action – a record of some act having been performed
      • e.g. nurse Dave administered Patient 1485756 with 15mg oral morphine at 12:25
    • other kinds
      • e.g. various kinds of administration statement
  • clinical statement – documentation of a statement with the same clinical statement context
  • clinical statement context
    • same subject of care
    • same ‘essential’ clinical time

      • = time when the states / events were true, time at which opinions are formed, time at which directive are issued, time at which acts are performed;
      • this doesn’t have to be a single time instant, it can be an interval of time, during which the patient state is assumed not to change in any significant way
    • same method / protocol / instrument, i.e. means of generating the statement
    • same observer (aka provider of information in 13606 & openEHR)
  • clinical statement core data – primary data expressing the state or event of the thing observed, or the opinion or directive being documented
    • in general, one or more data points
    • fine-grained time might be marked on individual items
  • ENTRY –  class or other model entity that formalises the clinical statement idea in an information model
    • provides a formal definition of clinical statement context items
    • has as content one or more core data items

According to the above:

  • An ENTRY should probably be a ‘pure’ model of the statement, rather than some particular optimisation of the data; if not, we’ll never have a clear statement of what the statement really is, distinct from various transformations of it for specific computing purposes, like querying
  • A core data element in an ENTRY corresponds to one atomic item (of potentially many) in a clinical statement (e.g. the systolic BP in the above BP observation example)
  • All data elements in an ENTRY have their context defined by the ENTRY
  • An ENTRY can’t contain another ENTRY, since there is no meaning to the idea of a ‘context containing a context’ (a ‘context’ is something like what philosophers call a ‘situation’, and is characterised by a conjunction of time / place / event / actors / …)

There are some remaining questions about whether some context items could be different in child items within an ENTRY. For the reader …

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About wolandscat

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