What is the difference between structural and semantic interoperability in health information exchange?

Structural interoperability relates to the format and structure of exchanged data, so data fields from one system can automatically populate appropriate fields in another system, often using standards such as Health Level Seven. Semantic interoperability requires data that is standardized or mapped to shared terminologies, allowing information systems to interpret, analyze, and act on the data, making it the highest and most complex form of interoperability.

The source distinguishes three levels of health IT interoperability: foundational, structural, and semantic. Foundational interoperability simply allows one system to receive data from another without interpretation. Structural interoperability is more complex and depends on consistent clinical terminology and meaning, enabling certain structured data fields, such as minimum data sets exchanged using HL7 standards, to populate automatically into the correct fields of the receiving system. Semantic interoperability goes further by requiring data to be consistent and codified, with standardized terminologies used or disparate terminologies mapped, so that systems can seamlessly exchange data, interpret its meaning, and populate fields appropriately. This true semantic level supports machine-to-machine data exchange and is essential for seamless health information exchange.