Exploring Methods of Implementing Arden Syntax for CDS Hooks.

Background: Specifications for Arden Syntax lack provisions for the standardized access of clinical decision support (CDS) services. The CDS Hooks standard provides such access.
Objectives: To extend an ArdenSuite reference implementation of the Arden Syntax by providing a CDS-Hooks-compatible interface.
Methods: With the use case Hepaxpert, an Arden-Syntax-based expert system for the interpretation of hepatitis serology test results, a needs analysis was performed to identify changes required in the ArdenSuite reference implementation to support the CDS Hooks API. Arden Syntax language support for CDS Hooks was also assessed.
Results: The needs assessment was performed in three phases: hook assessment, hook context definition, and Card definition. For the use case, the ArdenSuite was modified to include a new hook and hook context, which defines the type of CDS service as well its input parameters. Card definitions were created in the ArdenSuite. Examples of Arden Syntax support for the use case are presented for all three phases.
Conclusion: Minor changes in the ArdenSuite made it compatible with the CDS Hooks specification.