![]() ANSI/HL7 V3 IM, R1-2004 HL7 Version 3 Standard: Infrastructure Management: Message Control Act Infrastructure 10/20/2004 |
Responsible Group | Infrastructure and Messaging Work Group HL7 |
Control Query Co-Chair | Graham Grieve Kestral Computing Pty Ltd. |
Control Query Co-Chair | Mike Henderson Eastern Informatics |
Control Query Co-Chair | Joann Larson Kaiser Permanente |
Primary Contributor | Dale Nelson Zed-Logic Informatics, LLC |
Control Query Co-Chair | Jennifer Puyenbroek McKesson Information Solutions |
Primary Contributor | Larry Reis LR Consulting |
Primary Contributor | Mark Shafarman Oracle Corporation |
Control Query Co-Chair | Rene Spronk Ringholm GmbH |
Primary Contributor | Mark Tucker Regenstrief Institute for Health Care |
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Content Last Edited: 2011-07-13T15:38:54
HL7® Version 3 Standard, © 2004 Health Level Seven® International All Rights Reserved.
HL7 and Health Level Seven are registered trademarks of Health Level Seven International. Reg. U.S. Pat & TM Off.
Use of these materials is governed by HL7 International's IP Compliance Policy.
This is the normative material for Version 3, Release 1.
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The Message Control Act Infrastructure covers the alternate structures of the message Trigger Event Control Acts in the HL7 Composite Message. Refer to Transmission Infrastructure for details relating to the HL7 Composite Message.
Introduction
As discussed in Transmission Infrastructure Introduction, the "Trigger Event Control Act" contains administrative information related to the "controlled act" which is being communicated as a messaging interaction. A Trigger Event Control Act describes the 'action' that is happening to the subject of the message (the payload). The Trigger Event Control Act contains details about the trigger event for the message such as who, when, where and why.
In general, the Trigger Event Control Act Infrastructure is intended to promote the reuse of similar structures that are used for the same type of interactions across the domains that contribute content to the HL7 Version 3 messaging standard. This chapter will discuss the alternate forms of the Trigger Event Control Act and an overview of their intended use.
Trigger Event Control Act Categories
The Trigger Event Control Act includes general administrative information related to a controlled act that is being communicated as a messaging interaction. The Trigger Event Control Act varies in structure depending upon the type of message interaction. The categories of message interaction currently recognized are:
Accept-level acknowledgements are a message control function that do not require or allow a Control Act.
Application-level acknowledgement (functional response) message interactions require the Trigger Event Control Act and, in most cases, include a domain specific application response. Certain interactions will employ the use of Shared Messages as the functional response. Although the application acknowledgement (functional response) is normal, an application response message is also allowed to exist with only the Control Act that carries no additional domain content. If the response is not defined by a domain interaction, the use of a Transmission Infrastructure Interaction would be appropriate.
What follows is a brief discussion of each of the above message interaction categories.
Action, Information, and State Transition Control Interactions
These include all messages which convey application content with the exception of Query and Master File / Registry (see below). Messaging interactions occur between an originating application and a receiving application. For reliable messaging interactions, there is a sequence of at least two messaging events. Refer to Transmission Infrastructure for the modes of messaging. The initial message interaction generally passes application content that is the purpose for the messaging interaction sequence.
Depending on the receiver responsibilities of the initial message interaction, there might be a second message interaction that is some level of acknowledgement response. The acknowledgement could be by the receiving application or could be a surrogate for the receiving application that may only guarantee delivery of the content to the intended application.
Upon receipt of a positive application acknowledgment (response), the payload will indicate what was done (the promise, event, modified object, etc.). A negative application acknowledgement (rejection) won't contain any of those. The message interaction id and trigger event id indicate that this is a rejection.
The "semantic content" of a message is the combination of the ControlAct and the payload. To fully understand the trigger event you need both. The Control Act just says "Please 'do something' with 'this thing'". The payload is needed to indicate what 'this thing' is. However, the bulk of the trigger event information is attached to the Control Act:
Because this information tends to be reasonably consistent, irrespective of domain, the ControlAct has been defined as a reusable message type and will be referenced in the domain interaction. This saves committees the trouble of defining the content, simplifies their message types, and ensures consistency. However, the combination is needed to understand what is really happening.
Query Specification/Query Response Interactions
Query Specification and Query Response interactions have a form of the Control Act that contains elements that are needed to establish and control a logical query session between two applications. A more complete discussion of the use of the query support provided in this ballot is discussed in the Query Control, Query Infrastructure (QUQI) domain chapter.
Master File / Registry Act Interactions
Master File / Registry Act messaging interactions are the third and last category of message interaction types that require a unique Control Act structure in the current HL7 Version 3 Composite Message Payload Specification. This infrastructure is presented in detail in the Master File / Registry Infrastructure (MFMI) domain chapter.
Customization and Refinement of Trigger Event Control Acts
The message types defined in the Message Control Act Infrastructure section of the ballot are highly generic and inclusive. In order to permit expressivity where needed by implementers, most of the attributes and relationships are defined to be optional. The use cases for the general messages are so abstract that most useful constraints are impossible to specify at this level.
For example, in some cases, it is desirable to indicate a performer as well as an author, for an act. The performer is the party who actually performs the act; in this case, a notification. One can presume that there is an author for a control act, however it is not required to record information about the author. At the same time, while it is generally assumed that only a single author is allowed, many performers can be specified.
Note to implementers: Message designers and implementers may further refine and constrain Trigger Event Control Acts. Refer to Refinement, Constraint, and Localization section for details for rules and principles regarding customization and refinement.
Note to Technical Committees: Technical committees are encouraged to create refined versions of Trigger Event Control Acts that tighten the cardinalities of attributes and relationships as they see fit for their specific use cases. Unlike normal refinement, committee level Trigger Event Control Act R-MIM may not omit mention of attributes and relationships nor mark them as Not Permitted (NP). To do so would prohibit the use of these attributes in site-specific implementations. Refer to Refinement, Constraint, and Localization section for details for rules and principles regarding customization and refinement.
Diagram
This D-MIM (which is a duplicate of the R-MIM for this domain) specifies the Trigger Event Control Act structure in the HL7 version 3 composite message payload specification that is used for action, information, and state transition message interactions. This structure specifies the superset of associations and ActRelationshipTypes that domain committees may want to specify for administrative information content that is to accompany a given message interaction. Provisions for constraining the accompanying information will be made first by committees concerning functional needs for a specific message interaction. Further constraints will be provided by the enforcement of a conformance profile at the time of specifying the implementation of the message interaction.
The Trigger Event Control Act plays a central role in the semantics of HL7 communication. Information in the transmission wrapper helps with message delivery. The Trigger Event Control Act specifies precisely the nature of the event notification, or the command that is given. The central construct in the trigger Event Control Act is the ControlActProcess class.
The ControlActProcess class can be seen as a generalization of the HL7 Version 2 "EVN" (event) segment. The EVN segment specifies the name of the event as well as the time of the event, the person responsible for the event, etc. These tend to be "facts about the event", rather than "facts of the event".
There is inherent tension between the two different ways of representing information about the event. Data about the event can be carried by the ControlActProcess class, or by specific HL7 domain payload.
Consider a new order for service. In this case, there is a natural HL7 domain content payload (the "Order") which represents the order, and who ordered it and when, etc. For these messages, there will be a certain level of duplication between the ControlActProcess associations and the domain content.
It is an HL7 design philosophy *not* to duplicate information in ControlActProcess associations that is reasonably found within the carried Domain payload. Some duplication may however be unavoidable. HL7 message senders should not need to "pluck out" data from the domain content in order to populate the ControlActProcess associations. The full richness of the ControlActProcess is available as a standard design for use by messages that may need to convey this data. Using the pre-defined associations and attributes of the ControlActProcess will contribute to HL7's uniformity and consistency.
The control act process class is the central construct for the transmission wrapper RMIM. It captures information related to the specific act - the trigger event - that is central to the message.
The following attributes are central to using the control act:
Example: Suspension of a prescription. A doctor wants to suspend a prescription effective at noon the following day. The effective time would be noon the following day Numerous interactions might be triggered (order-entry system to pharmacy, pharmacy to nursing system). The time associated with each of the messages associated with those interactions would be the message time.
This attribute shall not be valued if a (detailed) reason for the Act is specified by means of the DetectedIssueEvent class. See below for a discussion of the reason act relationship and the reporting of detected issues in the DetectedIssueEvent class, the reasonCode attribute and the Transmission Wrapper.
The following control act participations are defined for the control act. Note that where the model permits more than one instance of (or requires) a participation or act relationship, cardinality should be constrained as fully as possible in the domain-defined message type. Note that the location for any of the participants, if provided, will be defined in the R_AssignedPerson CMET.
The author of an act is the person who takes responsibility for its creation. This could be the doctor who orders a test or the public health professional who decides to notify a local, state, or national public health entity.
The performer of an act is the person who actually and principally carries out the "controlled act". The performer is rarely used.
The actual party involved is either a device or a person, and the particular information involved is specified in the Assigned Person, and the Assigned Device CMET. The reader should note that, in many cases, it is the organization responsible for authoring or performing an act that is recorded as opposed to the person. In this case, the Assigned Person CMET is still used. However, the organization that scopes the performer role is recorded.
To convey an organization instead of person, leave the player empty and use the scoper.
Reporting Errors and Issues
An application which processes a message may detect various errors and issues related to the structure or the content of a message.
The reason act relationship is used to convey detected issues. Following is a list of reason's attributes:
Refer to the Detected Issue Event R-MIM Walkthrough for details regarding the DetectedIssueEvent that can be used to convey observations made by a system as part of it's processing of a message.
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