Thank you for the invitation to speak to this panel on the subject of Message Format Standards on behalf of Hewlett-Packard and the Andover Working Group.

Hewlett-Packard is a leading vendor of computer hardware and software systems, clinical measurement instrumentation and information systems, bioscience instrument systems, and laboratory data and information management systems.

The Andover Working Group, consisting of over 300 member organizations, was founded by Hewlett Packard in 1996 with the objective "To accelerate and broadly deliver standards-based solutions for healthcare which feature plug & play interoperability across the continuum of care."

Hewlett-Packard and the Andover Working Group believe that heterogeneity is a fact of life in the healthcare information infrastructure today and for the foreseeable future.(1) Independent of whether heterogeneity is the result of a "best of breed" architecture, consolidation of formerly independent organizations, or of government mandates for electronic communication of healthcare information, interoperability of healthcare information in a heterogeneous environment is a top priority of healthcare information technology executives.

Healthcare Message Format standards, which mirror the loosely coupled organizational model of much of the healthcare information infrastructure, represent an important paradigm in the communication of both administrative and Patient Medical Record Information (PMRI) in a heterogeneous environment.

The experience of the Andover Working Group is that precisely defined profiles for message format standards, coupled with component middleware supporting implementation of those standards, offers the potential for significant acceleration of the adoption of message format standards.

Attempts to establish an authoritative definition for the structure and content of the Patient Medical Record have proven to be elusive thereby complicating the issue of providing a precise definition of PMRI.

The Institute of Medicine provides the following definition for the patient record.(2) "The patient record is the repository of information about a single patient. This information is generated by healthcare professionals as a direct result of interaction with a patient or with individuals who have personal knowledge of the patient (or with both)."

AHIMA, (3) in providing a description of the health record, includes contents such as the identification sheet, problem list, medication record, history and physical, progress notes, physician’s orders, imaging and x-ray reports, electrocardiogram’s, lab reports, immunization record, correspondence, authorization forms, operative reports, anesthesia reports, pathology reports, recovery room records, vital signs graphics sheet, and discharge summaries.

The IOM distinguishes between a primary patient record and a secondary patient record. "A primary patient record is used by healthcare professionals while providing patient care services to review patient data or document their own observations, actions, or instructions. A secondary patient record is derived from the primary record and contains selected data elements to aid non-clinical users (i.e., persons not involved in patient care) in supporting, evaluating, or advancing patient care."

PMRI supports the workflow associated with the care of a single patient by supporting communication among healthcare professionals for purposes of planning and delivery of care and by providing a legal record for verification of services and treatment. When aggregated, PMRI provides the basis for population based research.

The multiple users and uses of PRMI imposes a requirement for comparable PRMI, which will be defined as semantically equivalent alternative representations. Information represented as an abstract data type can be mapped to and between alternative representations without semantic loss. For example, the notion of a temperature can be represented in terms of either ° F or ° C and can be converted between the two with no semantic loss.

Reasons for choosing alternative representations might include efficiency, consistency, or convention. For example a real-time communication of patient monitoring information imposes different constraints on representation of waveform information than does the need to capture a snapshot of a particular segment of waveform for inclusion in the patient record. While standardization on a single uniform representation may be possible, it may not be practical, particularly when migration from contemporary systems is considered.

The degree of semantic congruence required for comparable PRMI is dependent upon the specific intended use of the information. It is not possible to generalize regarding the allowed degree of mismatch without specification of the intended use.

The work of IEEE 1157,(4) CEN TC 251,(5) and HL7(6) has established that it is possible to map a common information model to and between a variety of interchange formats without semantic loss. Conceptually, each interchange format can be described in terms of an abstract syntax and concrete encoding rules. The choice of a particular syntax is guided by tradeoffs in terms of expressiveness, efficiency, and extensibility. Expressiveness determines what concepts can be represented, efficiency determines the consumption of computational resources in terms of processing and bandwidth requirements, and extensibility defines the ability to represent new concepts in a transparent manner.

For a number of historical reasons, based upon the initial focus of the respective SDOs, a variety of syntaxes and encoding rules have evolved. HL7, X.12 and other SDOs which initially focused on information which could be conveniently represented as text, developed approaches which led to positional, ASCII based encoding of information. DICOM which was faced with representation of images and IEEE 1073 which focused on the real-time interchange of parameter, waveform, and graphic information chose syntaxes and encoding rules appropriate to the efficient representation of multimedia data types.

Two methods have arisen for dealing with information described using different syntaxes and encoding rules. The first method involves encapsulation of one syntax/encoding in another. The second involves mapping between the different representations.

Work on encapsulation has been undertaken by HL7 for incorporation of DICOM images in HL7 messages and by X.12 and HL7 for inclusion of HL7 content in X.12 messages.

The Andover Working Group has done initial work on the mapping of information between IEEE 1073 and HL7. This work has been facilitated by the existence of an explicit information model and rules for mapping of the information model by both IEEE 1073 and HL7.

Preliminary work by HL7 on the use of XML as an interchange format shows significant promise and is an indication of the ability of the private sector to make progress in this area.

As noted earlier an architectural model describing the mapping of a common information model to a variety of interchange formats has provided the basis for approaches to interoperability among various SDOs for message format standards.

While message format standards represent an important approach to communication of comparable PMRI, other approaches to interoperability, such as document management, visual integration, and distributed database approaches, will benefit from the development of a common information model.

The work of HL7 on the version 3.0 Reference Information Model is a significant example of the ability of the private and government sectors to work together in the open standards process.

One of the conclusions of the Andover Working Group is that the availability of middleware to support the implementation of standards is a key factor in accelerating the adoption of standards.

The work of the Andover Working Group , the MS-HUG ActiveX for Healthcare, the Common Context Working Group, and CORBAmed in the development of component based support for implementation of standards is an area showing much promise.

In recognition of the move to component based middleware HL7 has formed the Special Interest Group on Object Technology which is focused on messaging standards and the Visual Integration Special Interest Group which is focused on context management.

As noted earlier, the use of SGML/XML for implementation of document architectures is a promising approach for communication of comparable PMRI. The HL7 SGML/XML Special Interest Group is developing a framework of interoperable Document Type Definitions which is being coordinated with the HL7 Reference Information Model development.

The ANSI HISB, ISO TC 215 and HIPAA initiatives collectively provide an environment that promotes coordination of PRMI message standards.

In response to the questions regarding the role of the federal government regarding syntax, models, emerging technologies, and coordination relate to standards for communication of PMRI Hewlett-Packard believes that the federal government can have the greatest impact by :

• Removing legislative barriers to the implementation of a healthcare information infrastructure.
• Participating in both Accredited SDOs and Consortia affiliated with SDOs.
• Requiring the use of standards developed by Accredited SDOs by government agencies involved in the collection and dissemination of healthcare information.

On behalf of Hewlett-Packard and the Andover Working Group I thank you for the opportunity to comment on the subject of message format standards.

3 AHIMA. Patient Resource Center. http://www.ahima.org/consumer2/1main.html