This is the ValueSet that contains all the codes in Último nivel aprobado (https://interoperabilidad.minsal.cl/fhir/ig/nid/ValueSet/VSUNivelAprob) and Último nivel aprobado (https://interoperabilidad.minsal.cl/fhir/ig/nid/ValueSet/VSUNivelAprob). E.g. what you have to deal with if you get resources containing codes in either of them