The National Health Data Dictionary provides national standards for the broader health sector. This update reflects changes to data standards between 1 July 2010 and 30 April 2012. During this time 10 data set specifications, 23 data element clusters, 177 data elements, one classification and 20 glossary items have been added. Twelve national minimum data sets, two data set specifications, 96 data elements, five classifications and three glossary items have been superseded, and three national standards have been retired since version 15 of the NHDD was published.