Tuesday, April 28, 2009

Point to Point Messaging and Persistent Document Exchange

In a recent letter to the HITSP panel describing the interoperability needed for meaningful use, I discussed point to point messaging and persistent document exchange. Here are a few additional details about these approaches.

Point to point does not imply that one EHR is communicating with one recipient via a specialized interface for that interaction. Requiring a custom interface for every connection between two stakeholders would not be scalable. Point to point simply implies that a transient message is sent from a data source such as a cloud computing EHR hosting center to a data recipient such as an e-prescribing gateway, a healthcare information exchange, or payer.

In Massachusetts we use interface engines, gateways such as NEHEN, and community-based health information exchanges such as EHX created by eClinicalWorks to connect thousands of users in dozens of organizations via transient messages.

There has been debate in the informatics community about using point to point messaging as a means of interoperability. Some suggest that all EHRs should have consistent data elements to foster the most complete interoperability. Although a common information model will be helpful in the future, we need to implement "good enough" standards now to improve quality and efficiency in the short term.

Sending packages of content between organizations using a common web-based transport mechanism enables such high value data exchanges such as e-prescribing, lab data sharing, and administrative workflow.

Point to point messaging works very well for secure transmission of a content package between two stakeholders. To ensure that HITSP interoperability specifications using point to point approaches are sufficiently complete to test, we need to be very specific about the transport mechanism, as complete as possible listing the vocabularies/code sets, and as constrained as possible describing the package contents. ONC will soon release a Common Data Transport Extension/Gap document which illustrates the kinds of secure transport transactions we'll need to harmonize.

What are the disadvantages of the point to point approach?

a. It does not work for complex scenarios such as an Emergency Department requesting the lifetime clinical record of a person from all the places their data exists in the country. That requires a master patient index, a record locator service, or a national healthcare identifier. In the short term, there are enough high value provider to pharmacy, provider to provider, and provider to payer exchanges that waiting to solve the unique patient identifier problem is not necessary.

b. Auditing the transfer of clinical records between two organizations based on transient messages may be more challenging than exchanging persistent documents with a non-reputiable time/date stamp and signature.

c. Reconstructing a damaged clinical record by replaying transient messages from an interface engine may be harder than simply reassembling persistent documents.

While point to point messaging uses a transient message from source to destination, a persistent document transfer uses the HL7 Clinical Document Architecture (CDA r2) to transfer an XML document between two stakeholders. That signed document is persisted by the recipient, providing a very clear audit trail about what information was transferred, by whom, and for what purpose. Examples of persistent document exchange include discharge summaries, quality data sets, and population health metrics being sent from one organization to another.

To support meaningful use such as medication workflow, laboratory exchange, clinical summaries for coordination of care, and quality reporting, it's clear to me that we need both point to point messaging and exchange of persistent documents.

I hope this discussion clarifies the kind of short term exchanges that will accelerate interoperability. This morning I'll be in Washington at the NCVHS meeting testifying about meaningful use. I'll post my testimony on my blog as soon as it is delivered.

My personal opinion is that metrics for meaningful use of point to point messaging and persistent document exchange may include

* Using a product that incorporates HITSP specifications and is certified by CCHIT using its Laika tool to validate conformance
* Passing an online test with a vendor recognized as compliant with HITSP interoperability specifications such as Surescripts
* Participating in a production health information exchange organization which incorporates HITSP standards such as NEHEN

Over the next few months, the entire healthcare IT community will engage in a very important dialog which will finalize these details.

6 comments:

Healthcare Straight Talk said...

Our company developed a program called "point-to-point healthcare" with a very similar idea, but using web services as the backbone for information exchange. We developed the p2phc program using a platform we call "Healthspace." We took an additional step where we are using xml as the main form to store and transport data. It allows us to support a data/information exchange that is agnostic to the data layout, solving a more serious issue in healthcare that is mired in healthcare standards... many complicated standads with too many entitities in healthcare that are non-conforming. This is an industry that is extremely silo'd and extremely information rich.

For us, objects (docs, patients, services themselves) that can access a true SOA model is the key to interoperability on the server side and creating simple xml/xaml based readers on the presentation side allows for a rich and modern look and feel at the UI level.

We have built very powerful applications already, but our overall goal is to launch a developer network next year. What do we hope to accomplish? We want to maintain the framework and allow each healthcare service provider to develop and maintain their own web services. It's a flexible framework which allows healthcare service providers to interface with their own systems via web proxies (lots of companies already have web sites that can people can access information right?). The service provider defines the level of information they expose while maintaining their own intellectual property via web proxies or locally on the server.

With many services created, we pull the services together into working applications, allowing for interoperability of content and context.

Ultimately the healthcare industry limits itself on how to deliver content and context in a HIPAA compliant methodology. There must be a better way instead of creating complex standards and data layouts, which are sometimes the culprits behind slow adoption... we'll see.

Brian Ahier said...

Defining an appropriate and recognized Health Information Exchange (HIE) will be key...
Other entities besides the New England Health EDI Network will also continjue to develop, some with questionable benefit. What organization will determine which HIE is valid?

Green said...

In our earlier conversations you mentioned that McKesson had a team that is specialized in migrating data from old databases to Practice Partner. Can you put me in touch with them?

I would like to get a sense of how they provide this service, what systems they a have migrated and what the cost is.

Adam Hawkins said...

This is a great post. We, at www.visiontree.com / www.optimalcare.com / have been doing several point to point integrations out of pure demand and non interoperable EMR systems.

However, more and more clients are moving towards standardized interfaces for the data transmission and we are very happy to hear that. Depending on the community/specialty, some have more advanced systems than others (urology vs. ambulatory).

I hope your testimony proves fruitful!

Deborah Kohn said...

RE: While point to point messaging uses a transient message from source to destination, a persistent document transfer uses the HL7 Clinical Document Architecture (CDA r2) to transfer an XML document between two stakeholders. That signed document is persisted by the recipient, providing a very clear audit trail about what information was transferred, by whom, and for what purpose.


I agree. And unless I'm not understanding this correctly, other examples (in addition to the HL7 CDA) of persistent document transfer would use the the ASTM CCR, the "harmonized" CCD, or any other standardized data set to transfer an XML document(s) between stakeholders.


Additionally, also I support using PDF Healthcare (a Best Practices and Implementation Guide, not a standard) to simply and cost-effectively "transfer" the XML document(s) between stakeholders, such as the discharge summaries, the quality data sets, the population health metrics ... even the (unstructured) word-processed / text reports, electronic forms, digital diagnostic images, photographs, and signal tracings (e.g., ECGs). For example, if a consumer, provider, or provider organization must send a patient’s (structured) medication list and (unstructured) radiology exam result report to multiple physician offices – some with office EHRs, some without – the consumer, provider or provider organization is able to embed those documents in the PDF container and securely send them. If the reports were sent to a provider who does not have an EHR, the receiving provider can at least view the documents and / or print them to paper. Also, the receiving provider can print the documents to paper from his/her smart phone without the need of a computer! However, if the reports were sent to a provider who has an EHR, the EHR can consume the XML data in that PDF container and populate their EHR.

Football Matches said...

In our earlier conversations you mentioned that McKesson had a team that is specialized in migrating data from old databases to Practice Partner. Can you put me in touch with them?

I would like to get a sense of how they provide this service, what systems they a have migrated and what the cost is.


Recep Deniz MD

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