For the best answers concerning the Clinical Modeling I refer you to the openEHR list for clinical discussions.
Most persons actively involved in clinical modeling can be found here.
Do you know of any existing OBSERVATION that uses the Person State with History?
I haven´t found any, and I try to understand the difference between Person State with History-events and the events that is mandatory within data History.
Regards
Richard
Electronic Record Company B.V.
Distributor ofOcean Informatics
for Europe and the Middle East
Leidsevaart 594-596
NL-2014HT Haarlem
PO Box: 376, NL-2300AJ Leiden
Do anyone know of any existing OBSERVATION that uses the Person State with History?
I haven´t found any, and I try to understand the difference between Person State with History-events and the events that is mandatory within data History.
State information is optional, and is not needed if the data are meaningful on
their own. If it is recorded, it can either be as a History of its own (i.e.
using the OBSERVATION.state atttribute described above), or else as state
values within the EVENT instances in the OBSERVATION.data History. Both
methods are useful in different circumstances. A separate state history is
more likely to be used in a correlation study such as a sports medicine study
on heartrate with respect to specific types of exercise. In this method, the
state information is a History of Events whose times and widths neednot match
those of the History in the data attribute. The state data under this approach
generally express the condition of the subject in absolute terms, i.e. they
are standalone statements about the subjects state at certain points in time,
such as walking on treadmill 10km/h, 10o incline. The other method will be
used in most general medicine, e.g. for recording fasting and post glucose
challenge states of a patient undergoing a glucose tolerance test. (See the
Data Structures Information Model for more details). State values stored
within the data History represent the situation in the subject at the time of
the Event within the History and usually in relation to it, for example post
8 hour fast. Recording the latter example in an independent state History
would require an Event of 8 hours
duration called fast. The latter would be technically still correct, but
would be very unnatural to most clinicians. FIGURE 21 illustrates the two
methods of recording state.
I hope that clarifies the differences, but I am not aware of an "official"
openEHR archetype that uses the first approach.
Sebastian
It´s just that I can´t grasp the practcal use. Why can I not use "post walking on treadmill 10km/h, 10o incline" in state within the data history, just like in the example of "post 8 hour fast"?
It´s just that I can´t grasp the practcal use. Why can I not use "post walking on treadmill 10km/h, 10o incline" in state within the data history, just like in the example of "post 8 hour fast"?
because the way doctors think is:
- for something like GTT, they just want to see one graph, of the data
points (the glucose values), but each data point needs to know what the
patient state way (post fast or whatever)
- for sports medicine (as an example) they want to see two graphs, the
heartrate versus the treadmill speed/inclination, or somesuch.
The latter therefore can be most easily modelled in 2 separeate
HISTORYs, whereas the first is modelled as one, with each EVENT carrying
a patient state indicator.
Reading your examples I have the following questions:
GTT, “want to see one graph”. Are you talking about an Archetype or a Template?
I think you are talking Templates where clinicians want to see something.
They use in the template archetypes.
Archetypes are used to store information in the database.
When I store 10 Glucose measurements and patient states obtained at 10 different dates and times in the data base each as single point measurement using an Archetype each time to store that measurement,
and when I store 10 Glucose measurements and patient states obtained at 10 different dates and times as a times series in the data base using one Archetype,
can I retrieve all glucose data and patient states using one version of the Archetype or do have have to use one Archetype version with all measurements modeled separately and one Archetype with all measurements modeled as a time series?
Gerard
– –
Gerard Freriks, MD
Huigsloterdijk 378
2158 LR Buitenkaag
The Netherlands
I would argue that since OGTT is a very common test, it is an archetype
which it is - see the glucose result archetype. For the sports ones, I
would expect to see some archetypes as well, but I know very little
about this part of medicine.
I was not making any suggestions about which is used however, only
saying why the underlying reference mode is the way it is.
Reading your examples I have the following questions:
- GTT, "want to see one graph". Are you talking about an Archetype or
a Template?
I think you are talking Templates where clinicians want to see something.
They use in the template archetypes.
Archetypes are used to store information in the database.
When I store 10 Glucose measurements and patient states obtained at 10
different dates and times in the data base each as single point
measurement using an Archetype each time to store that measurement,
and when I store 10 Glucose measurements and patient states obtained
at 10 different dates and times as a times series in the data base
using one Archetype,
can I retrieve *all* glucose data and patient states using one version
of the Archetype or do have have to use one Archetype version with all
measurements modeled separately and one Archetype with all
measurements modeled as a time series?
this will be an application issue, since in reality more than one
different time-series measurement has been made (even if some of the
subsequent ones only have one sample). If one group of samples is indeed
made using the same protocol, as a single test, then it should be
represented as a single Observation with a single History containing N
(usually 3) Events.
