isPreferredSpecifies whether or not the language is preferred by the person for the associated method of expression."Indicates whether or not the Patient prefers this language (over other languages he masters up a certain level)." - HL7 FHIR, Patient.communication.preferred.
languageA language for which the Person has some level of proficiency for written or spoken communication."The language about which the Staff Member has some knowledge. HL7 recommends using ISO 639 as the suggested values in User-defined Table 0296 – Primary Language." - HL7 Version 2.8, LAN-2."The next of kin/associated party's primary speaking language." - HL7 Version 2.8, NK1-20."The patient's primary language. HL7 recommends using ISO table 639" - HL7 Version 2.8, PID-15."The ISO-639-1 alpha 2 code in lower case for the language, optionally followed by a hyphen and the ISO-3166-1 alpha 2 code for the region in upper case. E.g. "en" for English, or "en-US" for American English versus "en-EN" for England English." - HL7 FHIR, Patient.communication.language."A language the practitioner can use in patient communication." - HL7 FHIR, Practitioner.communication"The preferred language spoken by the client. This information is required by the United States Meaningful Use electronic health record incentive program." - HL7 Behavioral Health Record DAM R2, Client.preferredLanguage"Preferred spoken language of communication as expressed by the patient." - PCORnet Common Data Model, Demographic.Pat Pref Language_Spoken
methodOfExpressionThe means by which the person is capable of communicating in the language. Examples of method of expression would be written and spoken."The ability the Staff Member possesses with respect to the language." Possible values (in Table 0403) include: Read; Write; Speak; Understand; Sign. - HL7 Version 2.8, LAN-3.
proficiencyLevel"The level of knowledge the Staff Member possesses with respect to the language ability." Possible values (in Table 0404) include: Excellent; Good; Fair; Poor; Some (level unknown); None. - HL7 Version 2.8, LAN-4."A value representing the level of proficiency in a language." - HL7 V3.