Resource DeviceLog - Content4.21
A set of raw data produced by a device.
The resource name as it appears in a RESTful URL is [root]/devicelog/
There are 4 device related resources
The device capabilities and log resources are used when communicating with a device, either directly or indirectly. When a channel is opened with the device, or its proxy, it first sends the Capabilities resource, and then a series of log resources. The FHIR JSON format is used in this case. (TODO: What's the communication protocol?) The application that receives the log resources may choose to merge the log with the capabilities statement to create a device observation, which is suitable for wider use within a EHR/Clinical record context. The application that receives the log resources may choose to merge the log with the capabilities statement to create a device observation, which is suitable for wider use within a EHR/Clinical record context. The Device Capabilities and Device Log resources may be used in a RESTful context, but in many contexts this will not be very useful - the data should be converted to a Device Observation for normal RESTful use in a patient care context.
Structure of the Device Log4.21.0.1
A medical device emits a series of these device log resources on a regular basis. A device log is simply a list of items with a key, a value, and a set of flags. The only way to understand the contents of the resource is to match the device log to the device capabilities that provides the context for interpreting the data in the device log. The device log can identify the appropriate Device Capabilities resource explicitly, but generally this is omitted, and the applicable resource is the one that is sent prior to any device log resources being sent. The system receiving the data must keep track of the appropriate Device Capabilities resource.
Some devices may be configured to know the identity of the subject of the observations, so the device log also includes the subject. However many simple devices do not know the identity of the subject well, or even at all, and the subject information must be provided or completed by the recipient of the device logs based on local context.
The device log is a low level resource suitable for direct communication with devices. The data from the device is usually converted to aDevice Observation for general use in a patient care context. This process is described further below.
Resource Content4.21.1
<DeviceLog xmlns="http://hl7.org/fhir"> <!-- from Resource: extension, narrative, and contained --> <instant value="[instant]"/><!-- 0..1 When the data values are reported --> <capabilities><!-- 0..1 Resource(DeviceCapabilities) Explicit reference to the capabilities --></capabilities> <subject><!-- 0..1 Resource(Patient|Group|Device) Subject of the measurement --></subject> <item> <!-- 0..* An item of data --> <key value="[string]"/><!-- 1..1 Reference to device capabilities declaration --> <value value="[string]"/><!-- 0..1 The value of the data item, if available --> <flag value="[code]"/><!-- 0..* Information about the quality of the data etc --> </item> </DeviceLog>
Alternate definitions: Schema/Schematron, Resource Profile
A device log has little context, and does not have the full context to support integrating the data into the patient record. The usual process for feeding the data from the device log resource into the patient record is to convert it to a Device Observation.
To convert the data from a Device Log to a Device Observation:
Converting a Data Item to an Observation
Between the Device Item and the matching Device Capabilities information, the following information is provided:
The following table describes how to convert from value to the correct data type:
The following table summarizes the interpretation of the possible flags
Generally, as a rule of thumb, metrics and facets are components of the observation.
Search Parameters for RESTful searches. The standard parameters also apply. See Searching for more information.