PCD Profile RTM Proposal Detailed
THIS PROFILE IS CURRENTLY UNDER ACTIVE DEVELOPMENT UNTIL 2008-04-21
1. Proposed Profile: Rosetta Terminology Mapping [RTM]
- Proposal Editors: Paul Schluter & Todd Cooper
- Editors: Paul Schluter & Todd Cooper
- Date: N/A (Wiki keeps history)
- Version: N/A (Wiki keeps history)
- Domain: Patient Care Devices
- Contributors: John Rhoads, Jan Wittenber, Robert Flanders, Al Engelbert, Richard Roa, Susan Blyde, Ken Fuchs, Sam Carello and other IHE PCD participants
The primary purpose of the Rosetta Terminology Mapping (RTM) profile is to harmonize the use of existing nomenclature terms defined by the ISO/IEEE 11073-10101 nomenclature standard by systems compliant with PCD-01. The RTM profile will also specify the appropriate units-of-measure and enumerated values permitted for each numeric parameter to facilitate safe and interoperable communication between devices and systems.
The Rosetta Table also is designed to serve as a temporary repository that can be used to define new nomenclature terms that are currently not present in the ISO/IEEE 11073-10101 nomenclature standard. Based on our experience to date, approximately 40 to 50 new terms will be required, principally in the area of ventilator and ventilator settings. This could also serve as a framework for adding and reconciling new terms to support the IEEE 11073 ‘Personal Health Devices’ initiative.
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<Summarize in one or two lines the existing problem . E.g. "It is difficult to monitor radiation dose for individual patients and almost impossible to assemble and compare such statistics for a site or a population.">
<Demonstrate in a line or two that the key integration features are available in existing standards. E.g. "DICOM has an SR format for radiation dose events and a protocol for exchanging them.">
<Summarize in a few lines how the problem could be solved. E.g. "A Radiation Dose profile could require compliant radiating devices to produce such reports and could define transactions to actors that collect, analyze and present such information.">
<Summarize in a line or two market interest & available resources. E.g. "Euratom and ACR have published guidelines requiring/encouraging dose tracking. Individuals from SFR are willing to participate in Profile development.">
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2. The Problem
The majority of PCD devices use vendor-specific or proprietary nomenclatures and terminologies. As a result, even though information may be exchanged using standards-based transactions such as Device Enterprise Communication, semantic interoperability is not achieved until the content is mapped to a standard nomenclature. This mapping is often inconsistent and subject to loss of information (e.g. mapping from a specific term to a more generic term). Also given the lack of tooling, utilizing standardized medical device terminology in production systems is difficult and often cost prohibitive.
This profile will focus on identifying a core set of semantics that are shared between multiple devices within the same modality (e.g., physiological monitors, ventilators, infusion pumps, etc.) and then mapping them to a standard terminology. The RTM mapping effort will initially include numeric parameters and their associated units of measurement and enumerated values.
The RTM information should be represented in a uniform manner, such as by one or more XML files. This will facilitate use by production systems, but more importantly, facilitate comparison between vendors that have (or plan to) implement the nomenclature standard in their systems, with the following goals:
- identify terms that are missing from the standard nomenclature
- ensure correct and consistent use if multiple representations are possible
- ensure correct and consistent use of units-of-measure
- ensure correct and consistent use of enumerated values
During the development of the RTM, gaps in the standardized medical device terminology will be identified. In these cases, proposals will be made for adding the semantics to the appropriate terminologies. Although the immediate focus of the RTM profile will be to standardize the content in transaction profiles such as DEC, which are typically between a device data gateway and enterprise level applications, the standardized terms should also support direct device communication, enabling semantic interoperability literally from the sensor to the EHR.
The availability of the RTM information will also facilitate development of tools that can more rigorously validate messages, such as enforcing the use of the correct units-of-measure and correct enumerated values associated with specific numeric values. For example, ST segment deviation will be expressed in "uV" or "mV", rather than the traditional "mm". This will promote greater interoperability, clarity and correctness which will in turn benefit patient safety.
The consistent and correct use of a standard nomenclatures such as ISO/IEEE 11073-10101 and UCUM for medical device and system data exchange will facilitate further development of real-time clinical decision support, smart alarms, safety interlocks, clinical algorithms, data mining and other clinical research. This work can be also be expanded at a future date to support events and alarms, waveforms, device settings and other critical monitoring information.
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3. Key Use Case
A patient is monitored at home. A potentially life-threatening cardiac event is detected and reported to a remote monitoring service that confirms and forwards the event to his caregiver. The patient is subsequently admitted to the ER complaining about chest pain. A diagnostic 12-lead is taken followed by continuous vital signs monitoring or telemetry for further observation. Following a series of premonitory episodes of ST segment deviation, the patient exhibits short runs of ventricular ectopy that rapidly devolve into ventricular tachycardia and then fibrillation. The patient is cardioverted in the ER and scheduled for CABG surgery. During surgery, the patient is connected to well over a dozen medical devices (e.g. multiparameter patient monitor, anesthesia machine, multiple infusion pumps, bypass machine, etc.) and the data from these devices and systems is displayed in a unified and comprehensible manner and automatically charted. After successful surgery, the patient is monitored in the ICU. The patient is discharged a week later to continue his recovery at home, where, among other things, he uses a spirometer with a low-cost wireless interface to facilitate recovery. He also exercises while walking around in and outside the house attached to a wireless sensor that records and transmits his ECG via his cell phone to a remote monitoring service. The patient also has follow-up visits to cardiac rehab, where his ECG and glucose measurements are taken before and after exercise, with all the data also electronically recorded. This information is ultimately stored in the patient's personal health record and made available for a follow-up study regarding the cardiac medications he was taking.
The key point of this comprehensive but realistic use case is that the patient's data is "touched" by well over three dozen medical devices and systems designed and manufactured by nearly an equal number of different vendors. An essential first step towards achieving interoperability across all these devices and systems is that they use a shared semantic foundation.
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<To focus on the end user requirements, and not just the solution mechanism, and to give people trying to understand the applications concrete examples of the problems existing and the nature of the solution required. State the problem domain and outline the workflows in terms of the people, tasks, systems and information involved. Feel free to describe both the current “problematic” workflow as well as a desirable future workflow where appropriate. Remember that other committee members reviewing the proposal may or may not have a detailed familiarity with this problem. Where appropriate, define terms.>
4. Standards & Systems
ISO/IEEE 11073-10101 Health informatics — Point-of-care medical device communication — Part 10101: Nomenclature, First edition, 2004-12-15. Published by ISO and IEEE, 2004.
The ‘Unified Code for Units of Measure’ (UCUM), .
5. Technical Approach
The principal technical steps of the RTM profile proposal are described in Sections 5.1 to 5.4.
5.1 Create the Rosetta Terminology Mapping Table
Vendors, typically participating as a IHE PCD Device Observation Reporters, will contribute a table listing the numeric parameters they plan to support. Each row of the table includes the vendors displayed name and units of measure and the equivalent ISO/IEEE-11073 identifier and ISO/IEEE-11073 and UCUM units of measure, as shown below:
|R||Group||Parameter group label (informative)|
|M||PART||Code partition (decimal)|
|M||CODE10||Context-sensitive code (decimal)|
|M||CF_CODE10||Context-free code (decimal, calculated by Excel)|
|M||Vendor_Description||Vendor description of parameter|
|O||Vendor_DName||Vendor Displayed Name|
|M||UOM_IEEE||IEEE UOM (single, short list or _pointer)|
|M||UPART||IEEE Unit Code partition (decimal)|
|M||UCODE10||IEEE Units context-sensitive code (decimal)|
|M||CF_UCODE10||IEEE Units context-free code (decimal, calculated by Excel)|
|M||UOM_UCUM||UCUM UOM (single, short list or _pointer)|
|C||Vendor_Status||S Supported F Future|
|C||Vendor_Sort||Numeric index for sorting|
|O||Enum_Values||Enumerated values (short list or _pointer)|
|O||OBX-20||Site identifier enumerations for certain measurements|
|O||Vendor_VMD||Vendor IEEE 11073 ‘Virtual Medical Device’ identifier Reference ID|
|O||REF_ID_COMMENTS||Vendor-specific Reference ID comments|
|R||DataType||Physiologic data type (num, wav, evt, etc.)|
|C,O||Containment||e.g. VMD, ‘channel’ (TBD)|
The Status letter indicates whether an entry in the column is 'M' Mandatory, 'R' Recommended or 'O' Optional.
The REF_ID column lists the MDC Reference Identifier that is equivalent to the vendor's numeric parameter. If there is any uncertainty, a "_?" shall be appended to the MDC Reference Identifier (e.g. MDC_ECG_HEART_RATE_?). If the term is missing from the ISO/IEEE 11073 nomenclature, the vendor may propose an MDC Reference Identifier and append an "_X".
5.2 Identify implementation differences and resolve them
The tables submitted by the individual vendors will be merged into a single Excel spreadsheet to facilitate discussion and discussion.
The information initially submitted as an Excel spreadsheet will also be converted into an XML document. This will facilitate the use of tools such as XSLT to find differences. For example, XSLT can be used to create a list of the MDC reference identifiers and the vendors that selected it, and MDC identifiers that were selected by only a single vendor would be examined and compared with similar terms.
5.3 Identify missing terms and propose new terms to standards groups
It is likely that new terms will need to be added to represent new concepts and terms since the publication of the ISO/IEEE 11073-10101 nomenclature standard. Any missing or new MDC reference identifiers will be submitted to the appropriate standards group (typically IEEE 11073) to create and add the new terms to the relevant standard.
5.4 Generate final set of terms, units-of-measure and enumerations for testing
Any corrections or additions will be reflected back the vendor's table and a new version of the merge table (and XML files) will be created. This review-edit-merge cycle will be performed several times.
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Device Observation Reporter - The Device Observation Reporter (DOR) actor receives data from patient care devices (PCDs), including those based on proprietary formats, and maps the data to messages that provide consistent syntax and semantics before sending them to the Device Observation Consumer (DOC) or Device Observation Filter (DOF).
Device Observation Consumer - The Device Observation Consumer (DOC) actor is responsible for receiving PCD data from the Device Observation Reporter, the Device Observation Filter, or both.
Device Observation Filter - The Device Observation Filter (DOF) actor is responsible for providing PCD data filtering services based on the publish/subscribe predicates negotiated with the client DOC application.
The number of numeric parameters supported by the DOR, DOC and DOF transactions will be increased, but transaction syntax and sequencing will not be affected by this profile proposal.
Communicate PCD Data (PCD-01) Transmit PCD data to enterprise clients from a Device Observation Reporter (or Observation Filter for PCD-02) and Receive PCD data by a Device Observation Consumer.
Subscribe to PCD Data (PCD-02/SPD) Defines predicate(s) for communication of PCD data from a DOF to a Device Observation Consumer.
Although the number of numeric parameters supported by the DOR, DOC and DOF transactions will be increased, the transaction syntax and messaging will not be affected by this profile proposal.
New transactions (standards used)
Impact on existing integration profiles
New integration profiles needed
Breakdown of tasks that need to be accomplished
The tasks described in steps 5.1 to 5.4 are summarized below:
- Create a uniform tabular (or XML or database) representation that will facilitate comparison and discussion.
- Identify minor implementation differences and resolve them.
- Identify missing terms and propose terms that should be added to existing standard terminologies.
- Generate final set of terms, units-of-measure and enumerations for verification and validation.
6. Support & Resources
The following groups and their respective tasks have been identified:
- Vendors will need to contribute table rows, and have already done so.
- Within the IHE PCD and IEEE 11073 membership, discuss and resolve differences in implementation.
- Work with other standards and clinician groups to resolve difficult topics (e.g. ventilator mode terminology).
- Within the IEEE 11073 committee, formally define and approve new terms as required by this proposal.
A significant amount of work has already been by the six IHE PCD Device Observation Reporter (DORs), culminating with the display of the Rosetta Table (Version 1k) one one wall of the IHE PCD booth at HIMSS 2008. The files are located at (start with RosettaTable.1k.doc first).
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- Certain terminology concepts, such as common enumerations ventilator modes, have been historically difficult to achieve due to competitive and marketing reasons as well as the complexity of the problem. In these cases, achieving a common set of terms for communications interoperability will be an essential first step; vendor specific terms could be supported as non-normative "display strings" also conveyed in the messages.
- This effort will likely trigger a major update to the ISO/IEEE 11073-10101 nomenclature, and it is unclear that we have the manpower and resources to do this.
- At the present time, the ISO/IEEE 11073-10101 does not have a well established operating mechanism for periodically updating the nomenclature and distributing it to implementors.
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8. Open Issues
Minor: The repository for the Rosetta Terminology Mapping could be a spreadsheet or an XML file (or both). Although a final decision regarding this has not been made, using a Schema constrained XML document is currently the preferred approach due to its simplicity and ease of distribution.
<Point out any key issues or design problems. This will be helpful for estimating the amount of work and demonstrates thought has already gone into the candidate profile.>
<If there are no Open Issues at Evaluation Time, it is usually a sign that the proposal analysis and discussion has been incomplete.>
9. Tech Cmte Evaluation
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Effort Evaluation (as a % of Tech Cmte Bandwidth):
- 35% for ...
Responses to Issues:
- See italics in Risk and Open Issue sections