Heart Maps FAQs

  • What is a hospital separation?

    A hospital separation or ‘hospitalisation’ is a completed episode of patient care in hospital, where the completion can be the discharge, death or transfer of the patient, or a change in the type of care (e.g. from acute to rehabilitation).  

    The admission data excludes admissions where a patient has been transferred from another hospital.  Hospitalisation data includes admissions to private and public hospitals.

    The hospitalisation data comprise separations by principal diagnosis only. At the state and regional area (Statistical Area 4 and Statistical Are 3 for ACT), the Australian Heart Maps display separations for five heart diagnoses: Heart Attack, NSTEMI, STEMI, Unstable Angina and Heart Failure.

    The Heart Maps also present rates for ‘All Heart’ admissions (which combines NSTEMI, STEMI, Unstable Angina, and Heart Failure). 

  • What does age-standardised rate (asr) mean?

    The Australian Heart Maps present both unadjusted rate and age-standardised rates. Unadjusted rates are calculated as the number of events in a given period, divided by the population of the region (Using the 2016 ABS ERP to derive the population denominator for the relevant years of interest (2012 to 2016).

    Unadjusted rates allow comparison across regions of different population sizes and can provide an indication of the health service needs of a region. Age standardised rates (ASR) have been adjusted for the age distribution of the population.

    Asrs allow comparison across regions that have differences in both population size, and age distribution. If a region has a high ASR relative to another region, it means that there are factors other than age and population size that are driving the number of admissions or deaths, such as lifestyle risk factors like obesity and smoking.  See Technical report for how the asrs have been calculated.

  • What is a rate ratio?

    The ‘gap’ in hospitalisations between Aboriginal and Torres Strait Islander peoples and non-Indigenous Australians is presented in two ways: a rate difference and a rate ratio.

    The ‘rate ratio’ describes the relative difference between Aboriginal and Torres strait Islander peoples and non-Indigenous Australians.

    It is calculated as the ASR for Aboriginal and Torres strait Islander peoples divided by the ASR for non-Indigenous Australians.

  • What is a rate difference?

    The ‘gap’ in hospitalisations between Aboriginal and Torres Strait Islander peoples and non-Indigenous Australians is presented in two ways: a rate difference and a rate ratio.

    The ‘rate difference’ is the difference in age-standardised hospitalisation rates between Aboriginal and Torres Strait Islander peoples and non-Indigenous Australians

  • How is a ‘region’ defined?

    The Australian Heart Maps defines a region as being the 86 Statistical Areas Level 4 (SA4) and the 10 Statistical Areas Level 3 (SA3) regions in the ACT (a total of 96 ‘regions’).

    The Statistical Areas Level 3 and 4 are based on the Australian Bureau of Statistics Australian Standard Geographical Classification boundaries and are stable geographic areas with typically between 30,000 to 130,000 people (SA3) and 100,000 and 500,000 people (SA4).

    It is important to note that data suppression is applied to any region where there is insufficient data thereby resulting in fewer than 96 sets of estimates depending on the indicator of interest.

  • What is the SEIFA index? How is it calculated?

    SEIFA (Socio Economic Indexes for Areas) is the Australian Bureau of Statistics measure of disadvantage for areas.

    SEIFA is designed to convey social and economic conditions of an area using indictors of education, occupation, employment, income, families, and housing collected in the Census.

    The Australian Heart Maps use the 2016 SEIFA Index of Relative Socioeconomic Disadvantage (IRSD) which measures how disadvantaged an area is in relation to a base Australian score (1,000).  

    For ease of use, the SEIFA Index for Relative Socioeconomic Disadvantage (IRSD) scores are presented into five groups (quintiles) each comprising 20% of areas and ranked by socioeconomic disadvantage (with Quintile 1 representing the most disadvantaged areas and Quintile 5 representing the least disadvantaged areas).

  • Why do some areas have missing data?

    If the population for a local government area is less than 1,000 or there are fewer than ten hospital admissions, the hospital admission data is not displayed in order to protect patient confidentiality.

    Mortality rates are not available where the population in any age group in an area is less than 30, or where there are fewer than 20 deaths in an area, by gender. For more information, refer to the MORT books.

    Risk factor data is not presented for areas with populations under 1,000, or with a high proportion of their population living in non-private dwellings (hospitals, gaols, nursing homes, members of the armed forces) or very remote areas.

    Click here for more information. 

  • Why can’t I see rates by cultural background/country of birth at a local level?

    The Australian Heart Maps use the ABS’ Standard Australian Classification of Countries (SACC) (cat. No. 1269.0) to present national level hospitalisations and mortality data by Regions of Birth.

    Further disaggregation is not possible due to small numbers and patient confidentiality.

    Hospital admissions by Region of Birth are presented for 2012-2014 for ‘all-heart’ admissions (not by diagnostic group).

    CHD Mortality by Region of Birth is presented for 2012-2016 at a national level only. Risk factor data is not available by Region of Birth.