BACKGROUND:
Immunization registries are utilizing HL7 more and more. Though currently, the primary use of HL7 is to accept batch data from external system, many registries are on the verge of using HL7 to connect and query other registries both in and out of their home state. This presentation will focus on two of the prevalent options in using HL7 to communicate between registries.

OBJECTIVE:
To understand the need for registry communication. To understand the role HL7 plays in this communication. To understand the pros and cons of two popular solutions: Hub and Direct Connections. To understand how a specific solution may or may not satisfy certain requirements.

METHOD:
Experiences generated from designing and using multiple HL7 solutions in statewide immunization registries including state to state communications and in-state communications.

RESULT:
HL7 is considered a national health communications standard. The HL7 guidelines define the manner in which the data message is formatted. The solutions that HL7 can be utilized in are many. Registry to Registry communication is just one solution. Regsitries have many similarities in the data collected however the manner is which they are operationalized and legislated may be different. The solutions discussed are the two most prevalent that address many of the barriers in multi registry communications. There are pros and cons for each.

CONCLUSION:
Much discussion and effort are put forth is deciding whcih HL7 architecture is best for a given area. Registry managers need to know the differences in the HL7 solutions available.

LEARNING OBJECTIVES:
1. Understand how HL7 is utilized in registry to registry communication.
2. Understand the "Hub" architecture and its strengths and weaknesses
3. Understand the "Direct Connection" architecture and its strengths and weaknesses