APPENDIX DIFFERENCES BETWEEN COLLECTIONS
BIRTH REGISTRATIONS COMPARED TO THE PERINATAL DATA COLLECTION
Birth registrations data in this publication are not the only births data available in Australia. The National Perinatal Epidemiology and Statistics Unit of the Australian Institute of Health and Welfare (AIHW) also collects birth data from midwives and other health professionals who attend births. These data are published annually in Australia's Mothers and Babies (Hilder L, Zhichao Z, Parker M, Jahan S, Chambers GM 2014. Australia's mothers and babies 2012. Perinatal statistics series no. 30. Cat. no. PER 69. Canberra: AIHW).
As information from these two collections are from different sources, the number of live births may vary. Notably births from the Perinatal Data Collection are released on a year of occurrence basis, while registered births from the ABS Birth Registrations collection are predominantly released on a year of registration basis. The Perinatal Data Collection reported the occurrence of 309,861 live births in Australia in 2012 (the latest available data), 0.1% more than the 309,600 births registered in the same year. Prior to 1994, the Perinatal Data Collection showed fewer births than births registered. This position then reversed, with more births recorded in the Perinatal Data Collection than births registered, returning in 2007 when births registered became greater. From 1998 the size of the difference between the two collections has varied between 0.05% and 3.4%.
While it is difficult to explain the differences, the greater number of births in the Perinatal Data Collection until 2007 may have been due to improvements in quality and coverage, particularly with the introduction of a perinatal National Minimum Dataset (NMDS) in 1997 which developed national standards for the collection of perinatal statistics. The trend may also reflect that parent(s) delay or fail to register the birth of a child.