Architecting the Health Enterprise with TOGAF 9

Several factors are currently driving the increased complexity of health information technology (HIT). These factors include: a new regulatory framework, innovations in the practice of healthcare delivery, standardization, cross-enterprise integration, usability, mobility, security, privacy, and the imperative to improve care quality and reduce costs.

A methodology and governance framework is needed for creating a coherent and consistent enterprise architecture (EA). The latter should not be driven by vendors and their offerings. Instead, health enterprises should develop an EA that is aligned with their unique overarching business context, drivers, and vision. Developing an architecture capability that is based on a proven framework should be a top priority for health IT leaders.

TOGAF 9 is an Open Group standard that defines a methodology, standardized semantics, and processes that can be used by Enterprise Architects to align IT with the strategic goals of their organization. TOGAF 9 covers the following four architecture domains:

• Business Architecture
  
• Data Architecture
  
• Application Architecture
  
• Technology Architecture.
  

The diagram below from the TOGAF 9 documentation provides an overview (click on the image to enlarge).



The Architecture Development Method (ADM) is the core of TOGAF and describes a method for developing an enterprise architecture. TOGAF 9 includes specific guidance on how the ADM can be applied to service-oriented architecture (SOA) and enterprise security (two areas of interest in health IT). The different phases of the ADM are depicted on the following diagram (click on the image to enlarge).



The Architecture Capability Framework provides guidelines and resources for establishing an architecture capability within the enterprise. This capability operates the ADM. The Content Framework specifies the artifacts and deliverables for each Architecture Building Block (ABB). These artifacts are stored in a repository and classified according to the Enterprise Continuum.

The Open Group has been working on the adoption of an open EA modeling standard called ArchiMate. ArchiMate provides a higher level view of EA when compared to modeling standards such as BPMN and UML. It can be used to depict different layers of EA including business processes, applications, and technology in a way that can be consumed by non-technical business stakeholders. A sample of an ArchiMate enterprise view of a hospital can be found here.

HL7 has published the Services-Aware Interoperability Framework (SAIF), an architectural framework for facilitating interoperability between healthcare systems. SAIF includes the following four components: the Enterprise Conformance and Compliance Framework (ECCF), the Governance Framework (GF), the Behavioral Framework (BF), and the Information Framework (IF).

For guidance on using SOA in healthcare, the Healthcare Services Specification Project (HSSP) has published the Practical Guide for SOA in Healthcare based on the TOGAF Architecture Development Method (ADM) and the SAIF ECCF. The Practical Guide for SOA in Healthcare contains a sample Reference Enterprise Architecture. The Practical Guide for SOA in Healthcare Volume II describes an immunization case study.

Also noteworthy is the HL7 EHR System Functional Model (EHR-S FM) and the HSSP Electronic Health Record (EHR) System Design Reference Model (EHR SD RM).