Page Comparison

In the openEHR Entry model, two types are used for 'observations' and 'evaluations'. As with any general terms, these terms are overloaded, causing confusion for some people. In the openEHR model, these two types have a clear purpose. The Observation type is used to record any information derived from the world outside the clinician's head (or any other clinical reasoning device) - i.e. any kind of phenomemon or state of interest to the clinical investigator in the care of the patient. Accordingly, the design of the Observation type defines its data as a History-of-events structure, since all phenomena observed in the external world are situated in time, and in many cases, there are multiple samples to be recorded. In theory, such information should be repeatably observable using the same protocol and assuming a sufficient level of skill or training on the part of the observer.
In contrast, the Evaluation type is used for recording clinical thinking rather than events from the outside world. Consequently, it does not oblige a historical timing structure. This is not to say that 'time' is irrelevant to clinical thinking. Indeed, many typical clinical assessments include all manner of times, as shown by this diagnosis archetype. However, the times in such evaluations are not the primary recording instance of phenomenon or event time of events that may be referred to in the Evaluation, but instead are summarised times, dependent on the kind of assessment being recorded. It may be that no event time is recorded in an Evaluation, such as for the goal archetype, where the only time indicated is future proposed date of achievement.

Thus the Observation type provides the structures for recording phenomena, including statements the patient may make, anything measured or sensed by the clinician, or via using a machine. The history structure provides a standardised way to include the event origin time, and offsets of each event in the series, if it is more than one. In addition, it provides 'state' and 'protocol' (the latter inherited from CARE_ENTRY) which allow the state of the patient (e.g. position, exertion level) and the method (e.g. pulse oximeter) to be recorded alongside the primary data (e.g. heartrate). The history structure of a typical observation is illustrated to the right.

137-OE.html?branch=1&language=1