The Clinical Document Architecture is a HL7 standard for the representation and machine processing of clinical documents in a way which makes the documents both human readable and machine processable and guarantees preservation of the content by using the eXtensible Markup Language (XML) standard. It is a useful an intuitive approach to management of documents which make up a large part of the clinical information processing arena.
CDA is being used also in electronic health records projects to provide a standard format for entry, retrieval and storage of health information. Many of the early CDA implementations eg discharge referral are of direct interest to Australian projects such as HealthConnect.
This is of much interest to those projects as the progress will help their understanding of the best data storage techniques for medical files. Storing patient files and health records is a key part of running a successful medical facility, and whether you are researching CDA or the best O2 business phones reviews to improve inter-office communication, it is important to find the best. CDA is most definitely a leader in its field.
All in all the development of a family of standards for interoperability under HL7 is somewhat inevitable. CDA and CCOW (a standard for compatibility for modules within a clinical health record of are both examples.
A new standard for conduct of business between different sectors has emerged electronic business XML (ebXML). The place of this standard and its position vis a vis HL7 needs exploration.
If you are planning to spend some of the summer break for catching up on some technical reading, you might want to buy The CDA Book! This very popular book recently published by eminent CDA expert Keith Boone is an easy and clear introduction to using HL7's Clinical Document Architecture. You will learn how to implement the CDA standard, understand its idioms, get easy-to-use implementation guidance with numerous examples and learn to "speak" the CDA language.
HL7 Australia, in conjunction with HL7 New Zealand, is happy to announce four one-day Workshops on the HL7 Clinical Document Architecture (CDA):
Auckland, NZ: Monday, Dec. 8, 2003 (Uni. Auckland, Room 234/Bld 733, Morrin Road, Glen Innes) Melbourne: Wednesday, December 10, 2003 (La Trobe University City Campus, 215 Franklin St, Melbourne) Canberra: Monday, December 15, 2003 (CSIRO Forestry House, Bank St., Yarralumla) Sydney: Thursday, December 18, 2003 (Oracle HQ, 4 Julius St., North Ryde)
The Workshops will be lead by Sandy Boyer, co-chair of the HL7 Structured Document Technical Committee. HL7 experts Stephen Chu (Auckland) and David Rowed (Sydney) have also agreed to participate. CDA is the standard XML representation of familiar clinical documents. This standard for managing documents is becoming increasingly important in all health systems. Click here for further information on CDA.
Workshop Program
9:00 - 12:30
Session 1 Introduction to CDA, international case studies on its use.
This session provides an introduction to the more technical session which follows and is designed for participants with a range of backgrounds including clinical, technical and policy/administration.
12:30 - 13:30
Lunch
13:30 - 17:00
Session 2 "Walk thru" of the CDA example document (a clinical progress note) used in the HL7 ballot, discussion on the Structured Product Label (the XML standard for approved drug product information), and consideration of the role of CDA for electronic discharge referral and HealthConnect document architecture standards. (Note: Depending on interest, the session focus may change and not all subject areas may be covered at each meeting.)
These workshops are being held in conjunction with a meeting to explore the potential for developing a common XML structure for drug information resources in Australia to make them more accessible and useful in an electronic format and integrated into clinical systems.
Workshop fees Australia: Full day: HL7 Members A$190; non-members A$240. Register for the CDA Workshops in Melbourne, Canberra or Sydney
Our thanks go to HL7 Australia Benefactor Member Oracle Australia and La Trobe University for supporting the Sydney and Melbourne Workshops.
Endorsements
The Australian Computer Society (ACS) is the recognised association for Information and Communications Technology (ICT) professionals, attracting a large and active membership (over 16,000) from all levels of the ICT industry. It provides a wide range of services to its members. A member of the Australian Council of Professions, the ACS is the public voice of the ICT profession, the guardian of professional ethics and standards in the ICT industry, with a commitment to the wider community to ensure the beneficial use of ICT. Visit www.ACS.org.au for more information.
Examples of CDA Applications:
PICNIC (Ireland, Denmark, Crete)
Regional Health Information System - Satakunta Macropilot (Finland)
SCIPHOX (pronounced Sky Fox) - Germany
Electronic Health Record at the University of Munster
MERIT-9 (Japan)
UK Staffordshire Emergency Health Record
CDA in Discharge Summary (Taiwan)
XML based Discharge letters University of Heidelberg
CDA in MAYO Clinical Notes 11 project
CDA and Prescription drug information
UK Care Pathway project
Other applications - Clinical Guidelines
Research/Development into CDA
Use of CDA in information retrieval
Structure of Dynamic Templates
Use of CDA in managing documents in distributed networks and access control.
CDA and the Electronic Health Record - Approaches to structure and validation
IBM Research - CDA in EHR
The Clinical Document Architecture is a Health Level Seven (HL7) standard for the creation of clinical documents using XML (extensible markup language).
XML is a process for adding (non-printable) characters to text documents to allow the computer system to process the text eg. change the format or presentation as in bolded text or to allocate specific meaning eg. storing data or encoding data embedded in the text. An simple example (of a complex system) would be: "This word will print as <bold> bold <\bold> and this word only". On screen this would appear as "This word will be printed as bold and this word only". Note: the use of the bracket structure is the method of embedding instructions in the text.
The CDA specifies the structure and semantics of clinical documents in health care (Dolin R, Alschuler L. et al. 2001). A document can be defined as a piece of text or information that would usually be authenticated by a signature eg. a progress note, a pathology request, a radiology report, or an account. A CDA document may contain text, images and multimedia, coded data. The CDA document can be:
Stored either permanently or temporarily as a document in a computer system; and b. Transmitted as the content of a message using E-mail, HL7 or any other messaging system.
CDA was created in the recognition that much of health care is involved in creating and managing documents and the document paradigm is well understood by clinicians and administrators.
A clinical document has the following features which form the framework for the CDA.:
Persistence
Stewardship
Authentication
Wholeness and context
Human readability
CDA aims to give priority to documents generated by clinicians in order to:
Standardise the format of the many thousands of typesof clinical documents
To support exchange of clinical information for human readability, and information processing;
To promote longevity of information by separating the data from the systems that store it (to avoid obsolescence as occurs with technological processes and by being computer platform independent;
Allow appropriate local adaptation of the standard to meet national or specific user requirements.
Header - this contains the key descriptive information about the document (metadata) such as who wrote it, who is it intended for, type of document.
Body - this contains the text of the document which may be structured at least under key headings or sections. It is possible for the text to contain coded values. It is also possible to have not text information in the body such as an image of an x-ray (using the DICOM standard representation)
CDA has been developed in 3 stages: Level 1 through Level 3. Level one has a structured header and structured body of message with limited coding capacity for content. Levels 2 and 3 impose more structure to allow the representation of "context" or constrained fields and more coded data. The standard has been published for level 1 and level 2&3 are currently in draft stages.
CDA level 2&3 documents (along with the standard electronic health record architecture) require the use of templates and archetypes, which define the key information and context of complex health concepts such as family history or blood pressure.
