Suppression and non-published results
All data for an area were suppressed and marked as ‘n.p.’ (not published), if the number of rounded hospitalisations was between 1 and 4, or the estimated resident population of the area for the relevant cohort (age group, sex or total population) was less than 300. To manage confidentiality, consequential suppression was applied. This is the process of suppressing information which, whilst not necessarily confidential, may be used to derive confidential data.
Rates based on low numbers of events and/or very small populations are more susceptible to random fluctuations and therefore may not provide a reliable representation of activity in that area. For this reason, results for some areas were suppressed and marked as ‘n.p.’ to manage volatility. Rates were not reported if the number of hospitalisations was fewer than 20 or the relevant population was less than 2,500.
Results for the number of same-day hospitalisations, percentage of hospitalisations that are same-day, number of bed days, and average length of stay were suppressed if either of the above conditions were met, or the number of same-day hospitalisations was between 1 and 4 for an area. Consequential suppression was applied to manage confidentiality.
Consequential suppression was applied based on the following scenarios:
- Where one demographic group is suppressed (for example, 0–64 years), the corresponding demographic group (for example, 65+ years) is consequentially suppressed.
- Where a single chronic PPH condition is suppressed, a second chronic PPH condition is consequentially suppressed. Where a single acute or vaccine-preventable PPH condition is suppressed, a second acute or vaccine preventable PPH condition is consequentially suppressed.
- Where a single Remoteness Area is suppressed, a second Remoteness Area is consequentially suppressed (considered for each PPH category).
- Where a single SEIFA IRSD quintile is suppressed, a second SEIFA IRSD quintile is consequentially suppressed (considered for each PPH category).
- Where a single PHN is suppressed, a second PHN is consequentially suppressed (considered for each PPH condition).
- Where a single SA3 is suppressed, a second SA3 is consequentially suppressed (considered for each PPH category).
- For PHNs that follow the Australian Statistical Geography Standard boundaries: where a single SA3 within a PHN is suppressed, a second SA3 within that PHN is consequentially suppressed (considered for each PPH category).