Definition

Participation in breast screening refers to the proportion of women aged 50–74 who are screened in a 2-year period.

Participation is measured over 2-year periods to align with the recommended screening interval and is reported by Financial Years (FY).

Interpretation

Breast cancer screening participation rates have increased from 49.5% in 2020-2022 to 51.3% in 2021-2023, approaching pre-pandemic rates, in part due to the resumption of screening as well as a funding boost from the Victorian Government to the BreastScreen Victoria program to expand the number of screening sites and implement a range of capacity and community engagement initiatives, including:

• Opening a number of new screening sites.
• Extending clinic hours.
• Sending in-language SMS reminders in up to 20 languages to improve accessibility and awareness.
• Conducting outbound calls in up to 8 languages to provide personalised follow-up and support.
• Facilitating group bookings for multicultural groups in the North-Western RAS from 2021 to 2023 to ensure culturally sensitive engagement.

Following a data linkage project between BreastScreen NSW and BreastScreen Victoria, in 2021-2023, data for Victorian women who screened at NSW clinics was included for the first time. This change led to a significant increase in the participation rate for Ovens-Murray Public Health Unit (PHU), as the region is located close to the NSW and Victorian border. As a result, the participation rate for Ovens-Murray PHU in 2021-2023 is 48.9%. Due to this update in data reporting, the 2021-2023 participation for this region should not be compared to previous years.

Breast cancer screening participation was significantly impacted by the COVID-19 pandemic in the North Eastern PHU region. Many of BreastScreen Victoria’s capacity initiatives have been dedicated to improving participation rates in NEPHU.

As a result, amongst the metropolitan Local Public Health Units (LPHUs), NEPHU had the greatest increase in breast cancer screening participation rates with an increase of 8.7% from 2019-2021 to 2021-2023 compared to other metropolitan LPHUs.

Breast Cancer Screening Participation in Victoria (Financial Years 2015-2023)

1. Definition:

Breast cancer screening 2-year participation in financial years is calculated using:

• Numerator: Number of women aged 50-74 screened by BreastScreen Victoria in the 2-year reporting periods. Participation data includes participants with Victorian residential addresses only and excludes participants who received private mammography.
• Denominator: Australian Bureau of Statistics (ABS) estimated resident population (ERP) in Victoria.

2. Data sources:

BreastScreen Victoria data extract provided May 2024 - 2-year participation rate for 2015-2017, 2016-2018, 2017-2019, 2018-2020, 2019-2021, 2020-2022, 2021-2023 in financial years.

3. Population data is Australian Bureau of Statistics (ABS) estimated resident population (ERP) data:

• 2015 - 2017 - Reference period 2016 as at Aug 2018 (Final ERP)
• 2016 - 2018 - Reference period 2017 as at Aug 2019 (Revised ERP)
• 2017 - 2019 - Reference period 2018 as at Aug 2019 (Revised ERP)
• 2018 - 2020 - Reference period 2019 as at Aug 2020 (Revised ERP)
• 2019 - 2021 - Reference period 2020 as at Aug 2021 (Revised ERP)
• 2020 - 2022 - Reference period 2021 as at Aug 2022 (Preliminary ERP)
• 2021 - 2023 - Reference period 2022 as at Aug 2023 (Preliminary ERP)

4. The population data is subject to confidentialisation and randomisation processes. Accuracy to the last digit is not claimed and should not be assumed.

5. Data provided for future data requests and publications may not exactly match the figures in this report for the same time frame as they will reflect subsequent updates to the dataset.

6. For data from 2015-2017 to 2020-2022, participants only include women screened by BreastScreen Victoria (BSV) and with Victorian residential address at the time of screening.

Starting from 2021-2023, Victorian women who have screened at clinics in New South Wales are also included in the numerator.

Please note that data trends may show an upward bias for 2021-2023 data, especially for geographical regions near the VIC/NSW state border due to this additional inclusion.

7. Client addresses are assigned to geographic variables based on the client's complete address (i.e., street address, suburb, and postcode) via BSV geocoding software.

8. State-wide participation rate used by BSV is derived by aggregating participation rates by BSV regions, which are mapped via postcode.

Please note that there is a small variation of 0.1% - 0.5% in the above state-wide participation rate for all women aged 50-74 years versus the aggregated rate by LGA.

9. Local Government Areas (LGA) were assigned to individuals by BreastScreen Victoria using BSV geocoding software:

BreastScreen Victoria liaises with the Australian Bureau of Statistics and uses a custom ERP file which includes LGA and five-year age group data.

10. To convert data from Local Government Area (LGA) to Local Public Health Unit (LPHU), mapping document provided by the Department of Health was used.

11. During the COVID-19 pandemic, local public health units (LPHUs) were created to oversee local cases and outbreaks of COVID-19. As of July 2022, the nine LPHUs (three metropolitan and six regional) have expanded their roles to include disease prevention, population health, and the investigation and response to notifiable conditions. They are now tasked with managing local cases and outbreaks for more than 30 notifiable conditions.

• Metropolitan LPHUs: North Eastern Public Health Unit, South East Public Health Unit, Western Public Health Unit
• Regional LPHUs: Barwon South West, Goulburn Valley, Gippsland, Grampians, Ovens Murray, Loddon Mallee

12. PHN data - participants include women screened by BreastScreen Victoria assigned to a Primary Health Network via their Statistical Area level (SA1)* region at the time of screening by BSV geocoding software.

BreastScreen Victoria liaises with the Australian Bureau of Statistics and uses a custom ERP file which includes SA1s, corresponding PHNs and five-year age group data.

13. Primary Health Networks (PHNs) are independent organisations that are funded by the Australian Government to oversee primary health care in their respective regions. PHNs evaluate the health needs of their communities and commission services to ensure that individuals can access coordinated care when and where it's needed. There are 6 Primary Health Network (PHN) regions in Victoria. 

• Metropolitan PHNs: Eastern Melbourne, North Western Melbourne, South Eastern Melbourne
• Regional PHNs: Gippsland, Murray, Western Victoria

14. Areas with smaller populations are also subject to greater variability, as sometimes a little change can have a significant percentage difference.

Where eligible population is zero or participation rate is over 100%, the rate was omitted and marked with an asterisk (*) in the tables.

15. Cells with a count less than 5 have been suppressed and are represented by #.

To ensure that the suppressed value cannot be determined by other values in the row or column, or by the row or column total, other values in the row or column may also be suppressed.

16. Please note that the pandemic impacted screening services and health seeking behaviours which will be reflected in the data in 2020-2022.