subject identifier A subject identifier is an identifier of a subject organism within the context of a particular investigation, study, or specimen extraction event. Damion Dooley This varies in its type (numeric or string) and its central repository depending on its context (use in a particular application/instance). Note: GSCID-BRC specification states " 'Host' is not the preferred term since some specimens may lack any detectable pathogen". In other words, a person would technically (logically) only have a host identifier AFTER they have been diagnosed as having a pathogen. A health care personal identifier, or a case identifier would be better than a more ephemeral "host id" individual organism identifier requires discussion