Health Level 7 (HL7)

Solutions we developed to meet the needs of health information systems like HIS, RIS and PACS provide data communication using the standard called “Health Level 7”. It consists of 7 layers as OSI model. Through this standard, accepted in March 1987, data can be transmitted between environments of healthcare. The aim of HL7 is to provide the communication between PACS computer applications. Platforms where systems like HIS, RIS and PACS run on use TCP/IP network communication protocol. To explain the role of HL7 in data transmission between information systems by an example:

To provide communication between Hospital Information System and Radiology Information System, firstly, an event like patient admission, transfer or discharge should happen. The main computer, which Hospital Information System is in, is responsible for tracking these events. This computer, Radiology Information System is also connected, sends a message to remote server. Since Radiology Information System is processing the next operation at that time, it does not expect this message. The format of this message is important; if it is in HL7 format, message is parsed, database is updated and acknowledgement is sent to confirm that the message is sent. If message is in different format, message rejection information has to be sent.

Today’s version of HL7, known as Version 2.x, has applied successfully in healthcare and developed day by day. HL7’s latest version, Version 3, has an object-oriented approach and its’ primary goal is to present an accurate and testable standard.