As a GP (family medical practitioner) I have been considering record systems
from the viewpoint of the questions I ask the record.
Not just at the point and time of care, but also afterward, over the whole
registered practice population, over the whole population at a time or over
all time and so on, but the main one because time is critical at the point
of care is the questions asked of the record at that time.
Going from this to the underlying structure of the data, I believe we must
accept that the systems will always be distributed, or at least the data
will be, since all care is never within the context of a single provider at
a single site and rarely within the context of facilities owned by a single
org. Even the NHS behaves far more like a cloud of loosely related
independent bodies than a single service (to the patient's detriment and
only partly repairable by fixing the record systems but I digress).
Thus an ability to store a pointer to information, together with a pointer
to scripts to authenticate with each of an arbitrarily large number of hosts
of information is needed. THis is current technology though. IMHO as much
as possible of this should be left outside the core of the medical record
system.
The system must also be prepared to act as a host in answering such requests
from elsewhere (with the patient's consent and so on).
This sort of approach seems to me to make it easier to preserve a relative
independence on the precise form of the underlying data storage - tables,
marked up files, and so on.
Envisage a large group of functions which will tend to have similar names (a
tendency reinforced by the publication of the names in use in various
projects) and return the same information. On the one hand they know the
sturcture of their own data tables etc, anod on the other hand they could be
called by several different programs, and on the third hand they can be
replaced one by one by identically named fucntions with identical output
dealing with wholly different underlying data stores, as commonality or
divergence occurs.
This is middleware of sorts.
