The position of the body when the observation was done, e.g. standing, sitting. To be used only when the body position in not precoordinated in the observation code.

The qualitative change in the value relative to the previous measurement. Usually only recorded if the change is clinically significant.

The focus of an observation when the focus is not the patient of record. In other words, the focus of the observation is different from Observation.subject. An example use case would be using the Observation resource to capture whether the mother is trained to change her child's trachestomy tube. In this example, the child is the patient of record and the mother is focal subject referenced using this extension. Other example focal subjects include spouses, related persons, feti, or donors.

A specific offset time in milliseconds from the stated time in the Observation.appliesDateTime to allow for representation of sequential recording of sampled data from the same lead or data stream. For example, an ECG recorder may record sequentially 3 leads four time to receive 12-lead ECG, see ISO 22077 .

This observation follows the target observation (e.g. timed tests such as Glucose Tolerance Test).

This observation replaces a previous observation (i.e. a revised value).

The Provenance/AuditEvent resources can represent the same information. Note that the Provenance/AuditEvent resources can represent the same information.