ISO 18812:2003 specifies general messages for electronic information exchange between analytical instruments (AIs) and laboratory information systems (LISs) within a clinical laboratory. It is applicable to the specialities of clinical chemistry/biochemistry, haematology, toxicology, microbiology, virology and immunology. It is not applicable to the blood transfusion and blood bank speciality

ISO 18812:2003 covers the specification of messages used by communicating parties and the syntax in which they are communicated. It does not cover the transport mechanisms used for the message interchange.

ISO 18812:2003 is applicable only to character-based message information. It is not applicable to the communication of graphical or image information.