Procedures data cubes

The data cubes can be used to explore a range of clinical data related to hospital separations. 

The Excel data cube workbooks consist of two sheets:

• Procedure Counts Data contains separation statistics by ACHI procedure by age group by sex by same-day status.
• Procedure Counts Summary contains a pivot table showing procedure counts by ACHI procedure code. This pivot table can be modified to various levels by right clicking on the table, selecting ‘Show Field List’, and then modifying the pivot table as desired (see Figure 1).
  • Variables in the ROWS list can be removed to disaggregate at higher levels.
  • Variables such as age group, sex and/or same-day flag can be dragged to the COLUMNS list to disaggregate by these variables.

Figure 1: Procedure counts summary pivot table

Source: Procedures and healthcare interventions (ACHI 11^th edition), Australia,2021-22 data cube.

Tips on using the Procedures data cube

Note that the use of the different editions of the Australian Classification of Health Interventions (ACHI) in the data cubes over time means that data across years may not be exactly comparable.

One or more procedures can be reported for each separation in the National Hospital Morbidity Database, but procedures are not undertaken for all hospital admissions, and so only a proportion of the separation records include procedure data.

Within the cubes, users can view the procedures by working down from the broad chapter level in the ACHI classifications to more specific categories (i.e. procedure code), as illustrated below.

• ACHI Chapter
  • ACHI Sub-Chapter
    • ACHI Block number
      • ACHI Procedure code

For example:

• 7. Procedures on Respiratory System (Blocks 520-572)
  • Lung and Pleura (Blocks 548-558)
    • Block 549 Incision procedures on lung or pleura
      • 38415-00 Incision of pleura. 

Users of the data cubes are likely to require some familiarity with the ACHI. Users will generally need to know what chapter the information they are looking for is in, to work down to more specific levels of detail. More information about the breakdowns and categories used within the data cube are given below.

Australian Classification of Health Interventions

The Australian Classification of Health Interventions (ACHI) is the Australian national standard for procedure and intervention coding in Australian hospitals, based around the Medicare Benefits Schedule (MBS). Guidelines for the use of the ACHI are contained in the Australian Coding Standards (ACS).

The ACHI has been structured with a principal axis of anatomical site. Within each chapter the anatomical site has been structured by a 'head-to-toe' approach. The secondary axis is procedure type, beginning with the least invasive procedure through to the most invasive procedure. Due to the historical development of the ACHI, code numbers do not always appear in numerical order within the tabular list. A third level axis, called a block, has therefore been introduced. Blocks are numbered sequentially in the tabular list to assist clinical coders in locating a specific code and have titles that relate specifically to the codes within the block. There are certain chapters that are an exception to the general format: Dental services, Obstetric procedures, Radiation oncology procedures, Non-invasive, cognitive and other interventions, not classified elsewhere and Imaging services.

The following is a list of the ACHI procedure chapters and the code ranges covered by each under Edition 12 of the ACHI:

Block numbers and procedure codes can vary across editions, with the same block numbers representing two different procedure groups. This should be taken into consideration when comparing data using different ACHI editions. Separate cubes exist for each of the ICD-10-AM/ACHI editions as it is difficult to map across editions.