In summary,the report complements Expenditure on health for Aboriginal and Torres Strait Islander people 2010–11 by providing a more detailed analysis of health expenditure estimates for Indigenous and non-Indigenous Australians in 2010–11.
Estimates are disaggregated at the regional level, as well as for specific disease and injury groups.
Health expenditure by remoteness
Expenditure was analysed for selected health services (i.e. admitted patients, Aboriginal Community Controlled Health Services, Medicare Benefits Schedule and Pharmaceutical Benefits Scheme). For these services, for every dollar spent per non-Indigenous Australian, $1.52 was spent per Indigenous Australian and expenditure increased with remoteness for both Indigenous and non-Indigenous Australians.
The difference was greatest in Remote/Very remote areas where, for every dollar spent per non-Indigenous Australian, $2.22 was spent per Indigenous Australian. The higher expenditure on Aboriginal and Torres Strait Islander people in remote areas is mainly due to higher expenditure on admitted patient services.
Health expenditure by disease group
The disease groups that accounted for the highest proportion of admitted patient expenditure for Aboriginal and Torres Strait Islander people were genitourinary diseases ($195 million, or 11% of Indigenous admitted patient expenditure), which includes the cost of dialysis treatment, followed by mental and behavioural disorders ($191 million or 11%), unintentional injuries ($149 million or 8%) and maternal conditions ($144 million or 8%). The largest disease group of admitted patient expenditure for non-Indigenous Australians was cardiovascular disease ($5,171 million, or 12% of non-Indigenous admitted patient expenditure).
Potentially preventable hospitalisations
Overall, for every dollar spent on potentially preventable hospitalisations (PPH) per non- Indigenous Australian, $2.22 was spent per Indigenous Australian.
The highest expenditure on PPH for Indigenous Australians was for chronic obstructive pulmonary disease ($36 million, or 16% of Indigenous PPH expenditure), followed by diabetes complications ($35 million or 16%) and cellulitis ($20 million or 9%). Expenditure on vaccine-preventable conditions was $21 per Indigenous Australian and $5 per non- Indigenous Australian.The authors comment that
Indigenous under-identification in hospital data
Hospital records should indicate whether an admitted patient is Aboriginal and/or Torres Strait Islander or non-Indigenous based on a question on the forms completed on admission. However, the question is not always asked or answered, and there is therefore a degree of under-identification of Aboriginal and Torres Strait Islander people in hospital records.
In 2013, the Institute released revised under-identification factors based on a study conducted in 2011 and 2012. These studies are undertaken on a five-yearly basis to monitor identification levels over time. The level of under-identification is assessed through a dataquality study that compares the results of face-to-face interviews where Indigenous status is ascertained with the information recorded in the patients’ administrative records. The results of this study represent the best information currently available on Indigenous underidentification in Australian hospitals.
Estimates of the level of Indigenous under-identification from Indigenous identification in hospital separation data (AIHW 2013b) have been used to adjust admitted patient expenditure in public hospitals. Under-identification factors can be used to estimate the ‘true’ number of records for Indigenous people by multiplying the number of Indigenous people in the hospital record by the weighted correction factor. In 2010–11, underidentification of Aboriginal and Torres Strait Islander people at the national level was estimated at 1.09% (AIHW 2013a). This suggests that the ‘true’ number of Indigenous people should be about 9% higher than indicated in the hospital record. The underidentification factor used in 2010–11 is a lower adjustment than used in 2008, 2007 (AIHW 2009) and 2005 (AIHW 2005b), which means that fewer hospital episodes have been reclassified as Indigenous. This has resulted in a slight decrease in Indigenous expenditure and a corresponding increase in non-Indigenous expenditure compared with the 2008–09 report. These changes represent an improvement in the methodology and a higher degree of accuracy in the estimates.
The under-identification of Indigenous Australians in public hospitals varies substantially between states and territories, as well as remoteness categories. In some states and territories, an average state-wide under-identification factor was applied to all hospital separations. In others, differential under-identification factors were used depending on the region in which particular service(s) were located.
As the AIHW studies on Indigenous identification in hospital data did not include private hospitals, an adjustment factor of 54% for private hospitals was derived from the analysis of linked hospital morbidity data from New South Wales (AIHW: Deeble et al. 1998). A loading of 5% is added to the Aboriginal and Torres Strait Islander patient costs to take into account known differences in comorbidity for similar Diagnosis Related Groups in Aboriginal and Torres Strait Islander patients. This has been done in each of the Expenditure on health for Aboriginal and Torres Strait Islander people reports since the one for the 1998–99 year (AIHW 2001, 2005a, 2009, 2013a; AIHW: Deeble et al. 2008).