LOINC, an acronym for Logical Observation Identifiers Names and Codes, is an international standard for coding and describing clinical and laboratory observations. LOINC is a transcoding language that allows you to read and interpret data from different operating systems, uniquely identifying exams that, although having the same name, test different things and, vice versa, aggregating under the same test code identical, but apparently different because of the strong idiosyncrasy of the names used at local level. The aim of the system is to codify the observation itself and not the value it can take, therefore, if we consider observation as a question (for example, what is the patient’s hemoglobin level X?) And the resulting value as an answer, LOINC provides the codes for the application (for example, 718-7: Hemoglobin: MCnc: Pt: Blood: Qn).

Within a laboratory can be used terms belonging to a local jargon, usually well understood among colleagues, but not sufficiently known to be used to communicate with the outside world U. Forsum et al.
The high level of detail of the LOINC system allows precise and timely transmission of laboratory data, making the results comprehensible, and therefore reusable, for the different care providers and thus avoiding the duplication of tests and examinations, time-consuming and money, especially in situations where accurate, clear and complete data is available is a key factor for the patient’s health.