HL7 Frequently Asked Questions
HL7 refers to data formats and standards used to structure and share medical data and patient health information (PHI). HL7 messages include information about specific medical or administrative events and are fundamental to interoperability. HL7 standards (e.g., V2, V3, CDA, FHIR) are created and supported by the non-profit standards organization Health Level Seven International. HL7 V2 is the most widely used version of the standard in healthcare.
1. How can I integrate different data formats like HL7, EDI and FHIR JSON into a single route and post to a database?
Interface Engines integrate different data formats to target systems by transforming them into a common format and then routing the data into the database. Watch the PilotFish Data Analytics & Reporting Video to see this demonstrated.
HL7, EDI & FHIR Data Integration for Reporting & Analytics
2. How are HL7 messages parsed?
Out-of-the-box, the eiConsole lenient parsing component handles anything that looks even remotely like an HL7 v2.x message – including “byzantine” sets of fields, components and sub-components that are not part of the standard. The lenient parser is exposed and enabled in the Transformation module. The HL7 message including any custom segments converts easily to XML.
HL7 to XML and XML to HL7 Transformation Module
3. How to create an HL7 interface end-to-end?
An HL7 interface for different message types has an import endpoint(s) for receiving messages, an export endpoint(s) for sending messages and a method of moving data between the two endpoints. Click on the video below to see how an HL7 ORU message coming from a hospital is then sent to a database using PilotFish’s Interface Engine IDE to build the HL7 Interface.
Building an HL7 Interface
4. Does PilotFish accept HL7 transactions and also have the capability of API calls?
PilotFish provides a consistent means to adeptly handle not only large batch-oriented data and standards transaction messaging, but also highly conversational XML and JSON APIs – including new versions of data formats or industry standards that you need. Configuration just requires changing a handful of options in the application.
5. What is HL7?
HL7 is a language that enables the standard, consistent and uniform exchange and processing of health-related information between systems. HL7 standards are developed and maintained by the healthcare IT standard-setting authority HL7 International. HL7 Version 2 or HL7 V2 is the most widely used messaging standard, there is also an HL7 V3. It facilitates the exchange of high volumes of pre-defined patient and clinical data across healthcare applications reliably.
6. What is an HL7 message?
Each HL7 message indicates the healthcare trigger event defined by the HL7 Standard. It defines the specific healthcare information being exchanged in each message type. The HL7 Standard identifies hundreds of data elements for communicating patient demographic, clinical, and financial information and describes the specific set or combination of segments that make up a properly formed message.
7. What are the most popular HL7 message types?
Each HL7 message sends information about a particular event – such as a patient admission via ADT (Admit, Discharge, Transfer). Message types have different sub-types. For example, there are over 50 different sub-types of ADT messages. Common HL7 message types include:
1. ACK – General acknowledgment
2. ADT – Admit, Discharge, Transfer
3. BAR – Add or change billing account
4. DFT – Detailed financial transaction
5. MDM – Medical document management
6. ORM – Order (Pharmacy/treatment)
7. ORU – Observation result (unsolicited)
8. SIU – Scheduling information unsolicited
8. Why is HL7 difficult to integrate?
HL7 is dubbed the “non-standard standard.” Every HL7 2.x implementation encountered will be different. HL7 messages typically contain a large number of specified data segments to start. The segments each can contain large numbers of individual fields. Segments and fields can be customized. To interface with another system or application, the messages need to map a common representation and not lose information. PilotFish’s eiPlatform lenient HL7 parser converts virtually any HL7-like message into XML without complex configuration.
9. How are HL7 message segments structured?
An HL7 message in the v2.x format is a collection of concatenated segments, each terminated by a carriage return. Segments occur in a defined sequence. Pipes | delimit fields, carets ^ are subfields. Depending on the type of field, each field can have multiple optional repetitions (separated with ~ by default), can be made out of multiple components (separated with ^ by default) where each of them can also have subcomponents (separated with & by default).
10. How to convert HL7 2.x message into XML and then convert XML into JSON?
The sequence would be HL7 message (either from directory listener or LLP) -> [Source Transform] HL7 Transformer (to convert HL7 to XML) -> [Target Transform] XSLT transform (to convert XML to JSON XML) -> JSON Transformer (to create JSON) -> Directory Transport (to write the file) via the PilotFish eiConsole automated assembly line process.
11. How to convert HL7 2.x message into XML?
The HL7 2.x message is converted to a common XML representation so that a single open-source W3C language, XSLT, can be used to transform the data. In the PilotFish eiConsole, a unique 3-pane graphical Data Mapper generates the XSLT transform to affect the data transformation to the XML or another format consumable by the target system.
12. What is a non-standard HL7 message?
The HL7 Standard specifies a data structure based on trigger events, segments, fields, and data types. Non-standard HL7 messages are created when different systems and applications require customizing and extending the standard. HL7’s structure allows optional fields or additional portions of messages. HL7 allows Z-segments (miscellaneous) for data elements defined locally.
13. How do you parse a non-standard HL7 message?
Middleware can handle the differences in data formats, varying versions of standards, and incompatibilities of working with extended versions. A highly lenient parser should easily deal with non-standards compliant and extended versions of HL7. A differencing engine mediates and identifies differences between HL7 2.x messages by performing gap analysis.
Differences in HL7 2.x Messages No Problem with PilotFish (click to enlarge)
14. How many different versions are there of HL7 2.x?
HL7 2.8 is the latest version. HL7 2.x versions include 2.1, 2.2, 2.3, 2.3.1, 2.4, 2.5, 2.5.1, 2.6, 2.7, 2.7.1, 2.8, 2.8.1 and 2.8.2. The v2.x standards are backward compatible. HL7 2.x earlier versions are currently the most widely used, but middleware solutions should support newer versions 2.7.1, 2.8, 2.8.1, and 2.8.2.
15. What is HL7 3.x?
HL7 3.x is a newer standard that has not supplanted HL7 2.x. HL7 V3 messages are based on XML. The Reference Information Model (RIM) is the foundation for HL7 V3 development. The HL7 V3 messaging standard defines a series of Secure Text messages (called interactions) to support healthcare workflows. Version 3 is not backward compatible with Version 2.
16. What is the HL7 v3 clinical document architecture standard?
HL7 2.x is in wide use; HL7 3.x is not. HL7 V2 (also called pipe hat) is based on older technology & is a delimited format separated by a pipe with headers and multiple segments. HL7 V3 messages are in XML format. Version 3 is not backward compatible with Version 2. The two versions work within completely different data structures.
17. What is interoperability in healthcare?
Interoperability is the ability of different information technology systems, devices, and software applications in healthcare to communicate, to exchange data accurately, effectively, and reliably, and to use the information that has been exchanged. Progress in data interoperability and digitization in healthcare addresses both syntactic and semantic interoperability.
18. What application software converts XML to HL7 and HL7 to XML?
PilotFish eiConsole’s graphical drag & drop data mapper component which is a graphical editor used to generate the XSLT transformations that transform the data format to any other data format. PilotFish provides a unique, robust triple-pane paradigm that supports mappings of any length and any complexity. Mapping remains graphically functional throughout.
19. How do you ingest HL7 files and export to a flat file?
PilotFish software supports HL7 ingestion over MLLP (Minimal Lower Layer Protocol). From there, the HL7 messages can be parsed into a common format that can be converted to an XML or flat file format.
20. What is the difference between HL7 and FHIR?
HL7 FHIR, based on modern RESTful web services and open web technologies, including XML, JSON and RDF, makes it easier for new apps and legacy systems to exchange very specific information, e.g., lab results. HL7 V2, HL7 V3, and CDA (part of HL7 V3) messaging standards are mature standards and remain in wide use for large volume push transactions.
21. What is an HL7 interface engine?
HL7 Interface Engines are software systems tuned to exchange healthcare information in huge varieties of use cases involving disparate systems communicating over different protocols. HL7 Interfaces Engines must adeptly handle data transformation and exchange of not only large batch-oriented data and all versions of HL7 messaging but also highly conversational XML and JSON APIs – including HL7 FHIR.
22. Why is interoperability important in healthcare?
Healthcare data interoperability is key to the ability of healthcare data to flow securely from one internal or external system to another, as needed, for patient care and patient use. Interoperability in healthcare must handle patient identification and privacy issues, complexities of messaging standards, data silos, legacy systems and technologies, and adaptation to modern applications.
23. Do you have a transformer to create outbound FHIR JSON, not just for ingestion?
For FHIR JSON we have JSON format builder that can take a sample FHIR JSON message as a sample and you can use that as your target mapping. The mapping generated from that will be translated to a normal JSON string in a target transformation transformer.
24. What is HL7 data integration?
HL7 data integration is the process of sharing and exchanging healthcare information between different systems using the Health Level Seven International (HL7) standards, which define the format and structure of electronic health data.
25. What is a typical HL7 integration workflow?
A typical HL7 integration workflow involves receiving HL7 messages from a source system, parsing and mapping the data to a target system’s format, validating and transforming the data, and finally sending the data to the target system. See How to Build HL7 Interface in 10 Steps.
26. How does an HL7 interface engine work?
An HL7 interface engine is a middleware tool that simplifies data integration by managing the communication, translation, and routing of HL7 messages between disparate healthcare systems.
27. What are some common challenges in HL7 data integration?
Common challenges include variations in HL7 message formats, data mapping complexities, data quality issues, maintaining compliance with privacy regulations, and integrating with legacy systems.
28. What is FHIR, and how does it relate to HL7?
Fast Healthcare Interoperability Resources (FHIR) is a modern, web-based standard developed by HL7 for exchanging healthcare data. FHIR uses RESTful APIs and supports JSON and XML formats, making it easier to implement and integrate.
29. How do I choose the right HL7 integration solution?
Consider factors such as compatibility with existing systems, ease of use, scalability, support for desired HL7 standards, and cost. Look for solutions with a strong track record and positive reviews from healthcare organizations. See Competitive Advantages of PilotFish’s integration engine.
30. What are the benefits of cloud-based HL7 integration solutions?
Cloud-based solutions offer scalability, flexibility, reduced infrastructure costs, easier updates, and remote accessibility, making them an attractive option for healthcare organizations looking to streamline HL7 data integration.
31. What is HL7 CDA, and how is it used?
Clinical Document Architecture (CDA) is an HL7 standard for exchanging structured clinical documents, such as discharge summaries and progress notes. CDA documents are XML-based and combine human-readable content with machine-readable structured data.
HIE Interface Example with CDA and HL7 Data
32. How do I validate HL7 messages for data quality and compliance?
Use validation tools to check HL7 messages for syntax, structure, and content compliance. Ensure that the data adheres to both HL7 standards and any regulatory requirements specific to your region or organization.
33. Can HL7 integration support real-time data exchange?
Yes, HL7 integration can facilitate real-time data exchange, enabling healthcare providers to access up-to-date patient information and make more informed decisions, improving patient care and outcomes.
34. How can I ensure the reliability of HL7 data exchange?
Implement monitoring and alerting systems, error handling mechanisms, and message tracking to detect and resolve issues quickly. Establish clear processes for data exchange and involve relevant stakeholders in integration planning.
35. Can HL7 messages be exchanged over different communication protocols?
Yes, HL7 messages can be exchanged using various communication protocols, such as TCP/IP, HTTP, Web Services, and FTP, depending on the requirements of the healthcare systems involved in the data integration. PilotFish middleware includes 40+ Listeners.
36. How can I handle data mapping complexities in HL7 integration?
Utilize data mapping tools, create comprehensive mapping documentation, and involve domain experts to ensure accurate data mapping. Regularly review and update mapping rules to maintain data quality and address changes in source and target systems.
37. How do I troubleshoot issues with HL7 data integration?
Investigate message logs, error reports, and system configurations to identify potential issues. Perform testing and validation to confirm the problem, and work with integration analysts, developers, and vendors to resolve any issues promptly. eiDashboard provides real-time operational reporting and management of your HL7 interfaces.
38. What is the HL7 Consolidated Clinical Document Architecture (C-CDA)?
C-CDA is a set of standardized templates based on the HL7 CDA framework, designed to streamline the creation, exchange, and integration of electronic clinical documents, such as care summaries, consultations, and referral notes.
39. How can I ensure the performance of my HL7 integration solution?
Monitor system performance, optimize message processing, and perform load testing to identify potential bottlenecks. Ensure adequate system resources and consider using a scalable cloud-based solution to handle fluctuations in demand. PilotFish offers on-demand licensing.
40. How do I handle versioning and backward compatibility in HL7 integration?
Maintain detailed documentation of HL7 versions and system configurations and use interface engines that support multiple HL7 versions. Implement version negotiation and conversion strategies to maintain interoperability and data quality.
41. How can I reduce the complexity of HL7 message processing?
Use an HL7 parser to extract, process, and manipulate message content more easily. Simplify message structures by removing unnecessary elements and using message templates to standardize the creation of HL7 messages.
42. Can HL7 integration support data exchange between EHRs and other healthcare IT systems?
Yes, HL7 integration enables interoperability between Electronic Health Records (EHRs) and other healthcare systems, such as laboratory information systems (LIS), radiology information systems (RIS), and pharmacy management systems. PilotFish healthcare integration solutions for all lines of business.
43. How do I handle internationalization and localization in HL7 data integration?
Use character sets and encoding that support multiple languages, and consider regional differences in data formats, units of measure, and terminology. Utilize HL7 standards, such as FHIR, that have built-in support for internationalization and localization.
44. What is the relationship between HL7 integration and healthcare analytics?
HL7 integration enables the collection and exchange of healthcare data, which can be aggregated, analyzed, and used to generate insights for improving patient care, streamlining clinical workflows, and enhancing the overall efficiency of healthcare organizations. Read our HL7 and data analytics case study.
HL7®, HEALTH LEVEL SEVEN®, CCD®, CDA®, and FHIR® are trademarks of Health Level Seven International.