The Australian health, community services and housing assistance sectors each have a national data dictionary. These dictionaries were developed as an authorative source of national metadata standards to support the reporting of consistent and comparable statistics in each sector.
Of the three sectors, the health sector was the first sector to develop a national data dictionary. The National Health Data Dictionary (NHDD) was published as the National Minimum Data Set for Institutional Health Care in September 1989. The next version was published in 1993 with subsequent versions published on an annual basis.
In 1996, coinciding with the preparation of version 6 and the development of the Knowledgebase, the underlying structure of the NHDD was amended to incorporate concepts from the international standard for the definition of data elements (ISO/IEC 11179).
The community services sector was the next sector to develop a national data dictionary. The National Community Services Data Dictionary (NCSDD) was first published in 1998. It also employed the same structures employed by the NHDD. Versions two and three of the NCSDD were subsequently published in 2000 and 2004.
The housing assistance sector first published the National Housing Assistance Data Dictionary (NHADD) in 2001 with the second version published in 2003. It employed the same structures used by the other two dictionaries.