Low birthweight is defined as less than 2,500 grams.

Excludes multiple births and stillbirths. 

Analysis by state/territory, remoteness and Socio-Economic Indexes for Areas (SEIFA) Index of Relative Socioeconomic Disadvantage (IRSD) is based on usual residence of the mother.

Data excludes Australian non-residents, residents of external territories and records where state/territory of residence was not stated.

Variability bands are to be calculated for single-year and aggregate years data by state and territory using the method below.

Presented as a:

• percentage, and 
• number (for disaggregations by Indigenous status).

100 × (Numerator ÷ Denominator)

Variability bands: to be calculated using the standard method for estimating 95% confidence intervals as follows:

CI (CR) = CR ± 1.96 x (CR/√d)

Where   d=number of live-born singleton infants.

CI = confidence interval

CR = crude rate (expressed as a percentage)

2012—Nationally by:

• remoteness (Australian Statistical Geography Standard (ASGS) Remoteness Structure)
• 2011 Socio-Economic Indexes for Areas (SEIFA) Index of Relative Socioeconomic Disadvantage (IRSD) deciles

2012—State and territory, by:

• Indigenous status of the mother

2010–2012—State and territory, by:

• Indigenous status of the mother

Disaggregation by Indigenous status of the mother is recommended to be reported using three-year combined data for the current reporting period due to the small number of low birth weight infants born to Indigenous mothers each year. Single year data (2012) will be reported for time-series (state/territory by Indigenous status).

Most recent data available for 2015 National Healthcare Agreement (NHA) performance reporting: 2012 (calendar year data).

Indigenous: Aggregated data (2010 to 2012) will be reported for the current reporting period (state and territory).

Single year data (2012) will be reported for time-series (state and territory).

Information is included in the National Perinatal Data Collection (NPDC) for all live births and still births of at least 400 grams birthweight or at least 20 weeks gestation. 

For 2011 data, the 2011 SEIFA IRSD quintile and decile data were produced using the Australian Standard Geography Classification geographical unit of Statistical Local Area. For 2012 data, the 2011 SEIFA IRSD quintile and decile data will be produced using the Australian Statistical Geography Standard geographical unit of Statistical Area 2.