As always when you try to standardize things, there are just some things that refuse to fit into any well defined or shaped bucket. My case in point today is the concept of "Procedure". I made the happy mistake of observing on the FHIR list that an HL7 RMIM being used to illustrate a question was incorrectly using the V3 Procedure to describe observations. After all, every V3 expert knows that the definition of Procedure involves the intention to change the state of the subject. This provides a fairly decent white line from which one can adequately classify distinguish acts whose principal intent is to gather data from those which are intended to do something to the patient. The reason this was a happy mistake is that it gives us the opportunity to think it over a complex and previously resolved but contentious issue in V3. Maybe we can do it better this time in FHIR.
That line is certainly blurred when you get into procedures like colonoscopy (where polyps can not only be observed but also removed), or coronary catheterization (with possible angioplasty or stent insertion). And there are other diagnostic procedures which have been known to also have a therapeutic effect.
However, medical nomenclature used by physicians, nurses, and perhaps most importantly, administrative staff make this distinction quite a bit troublesome.
I observed that a procedure often involves some degree of risk outside of the norm, but wasn't certain whether that was a useful distinction. Others observed that administratively, things like venipuncture have a procedure code and appear on the bill, but don't necessarily show up on the patient chart with any huge frequency nor have they much clinical significance (in most cases). Others point out that abdominal ultrasound probably has less risk to the patient than venipuncture (although perhaps not from the perspective of device manufacture).
One definition contributed by Cecil Lynch that I particularly liked is: "An Act that requires the alteration of the physical condition of the subject or the investigation of a body space not amenable to direct observation without instrumentation.” It sort of gets at the notion that this isn't the run of the mill observation or in-office activity. But again, we get to shades of gray that make it hard to figure out what to do with other procedures.
One of the things that I'd like to see is a clear distinction being made between "billable event", and the "clinically relevant" activity. What (usually) makes a procedure worth note to a healthcare provider? What does it tell them? Is it merely a point of reference and/or inference? Why would they care about it? Perhaps if we could get at the why, then we could get at the what.
Until then, and even afterwards, there will always be a big gray area. And I don't expect that will ever change until how we pay for care is much more aligned with how we provide it.
How would you describe it?