RID's that existed in a previous version of Radlex but should no longer be used as part of Radlex. This could be due to invadvertent duplications of terms, erroneous terms, etc. If a term is medically obsolete, i.e. is no longer used in the medical or radiological fields, but is an older term, it may be retained in Radlex with a note in the comment field as to its use or current lack thereof.