Updates to MedlinePlus Connect Web Service Formats

The National Library of Medicine announces several changes in the format of the MedlinePlus Connect Web service. MedlinePlus Connect facilitates the linking of patient portals and electronic health record (EHR) systems to MedlinePlus, an authoritative, up-to-date health information resource for patients, families, and health care providers.

MedlinePlus Connect conforms to the HL7 Version 3 standard for how these links are structured and function. Specifically, both the MedlinePlus Connect Web application and Web service accept URL-based queries in the format specified by the Implementation Guide for URL-Based Implementations of the Context-aware Knowledge Retrieval (Infobutton) Domain. Furthermore, the responses of the MedlinePlus Connect Web service follow the Implementation Guide for Service-Oriented Architecture Implementations of the Context-aware Knowledge Retrieval (Infobutton) Domain.

Changes in this latter specification required that we make corresponding changes in the Web service responses. These changes are:

• Enabled two new formats for the Web service, JSON and JSONP. These options are in addition to the XML format. Users can choose the response format by including the knowledgeResponseType parameter in their URL-based query. If this parameter is not used, the default response format is XML. These formats were enabled in December 2013.
• Small changes to certain Atom:feed node elements in our XML output. Specifically, the Atom:feed node no longer contains a reference to the v3 namespace, the Atom:feed:updated node no longer has the attribute "type=text", and the Atom:feed:category nodes have been simplified. These changes were enacted in April 2014. Note that the Atom:entry elements that contain the MedlinePlus and GHR content were unchanged.

Visit the Web Service Demonstration page to see samples of the different Web service formats (see Figure 1).

More information about the MedlinePlus Connect Web service can be found in the documentation. Additional information about HL7 standards can be found at www.hl7.org.