Notes on the data: Hospital admissions
Admissions by hospital type and sex; by principal diagnosis; and by procedure, 2012/13
Policy context: Admission to hospital is a formal process, and follows a decision made by an accredited medical practitioner at that hospital that a patient needs to be admitted for appropriate management or treatment of their condition, or for appropriate care or assessment of needs .
Patients are usually admitted to hospital either as an emergency or as a booked admission. Emergency admission patients are usually admitted through the Accident and Emergency Department: these are seriously injured or ill patients who need immediate treatment. Most patients receive hospital-based services as a booked (elective) admission, either as a same-day patient or an inpatient. A same-day patient comes to hospital for a test or treatment and returns home the same day. An overnight admission is recorded where a patient receives hospital treatment for a minimum of 1 night (that is, the patient is admitted to and separated from the hospital on different dates) or longer in the hospital.
The majority of people who have had an episode of care in a hospital express satisfaction with the service when they leave . However, admission to hospital carries with it a risk of harm. In Australia rates of serious adverse medical events are similar to those found in studies in the United States, with 0.3% of hospital admissions associated with an iatrogenic (medically caused) death and 1.7% associated with major iatrogenic disability . Admission to hospital per se also carries a risk of adverse events, in addition to those related to any medical treatment undertaken. These include a risk of cross-infection, injury, or rarely, death.
- Australian Institute of Health and Welfare (AIHW). Australian hospital statistics 2012-13. Health services series no. 54. (Cat. no. HSE 145.) Canberra: AIHW; 2014.
- Runciman WB, Webb RK, Helps SC et al. A comparison of iatrogenic injury studies in Australia and America II: reviewer behaviour and quality of care. The International Journal of Quality in Healthcare 2000;12(5):379-88.
The data presented are of the number of separations, or completions of the episode of care of a patient 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). In this atlas the term 'admission' is used in place of the more technical 'separation'. As these data relate to short-term episodes of care, and not to long-stay episodes, the number of admissions is similar to the number of separations in any year.
Note that the data are based on the count of all separations. As such, repeat admissions for one person are counted as separate admissions. In addition, patients admitted to one hospital and transferred to another hospital are counted as separate admissions. The impact of these hospital transfers would result in a higher rate of admissions in regional areas compared to the metropolitan areas, as well as for certain conditions which are more likely to result in transfers.
The national data exclude well babies (i.e., babies not admitted for acute care) who are nine days old or less, other than the second or subsequent live born infant of a multiple birth whose mother is currently an admitted patient. [For further information see Australian Institute of Health and Welfare. Australian hospital statistics 2012-13. Health services series no. 54. (Cat. no. HSE 145.) Canberra: AIHW; 2014.]
Same-day admissions for dialysis for kidney disease have also been excluded from the data in this atlas for the categories of admissions for males, females and total persons, and admissions by hospital sector, as they represent many repeat visits by a relatively small number of patients, who may have multiple admissions in a week: their inclusion can dramatically alter the geographic distribution of other categories of admissions (see the separate note for Same-day admissions for dialysis for kidney disease for further details); these data are presented separately. All other same-day admissions are included.
Details of data presented
Refer to separate note for Same-day admissions for dialysis for kidney disease.
Separate data are presented for:
1. Admissions by hospital type and sex (excluding same-day admissions for renal dialysis):
- Total admissions - Public (acute)/ Private (acute or psychiatric)/ All hospitals
- Male total admissions - Public/ All hospitals
- Female total admissions - Public/ All hospitals
2. Admissions by principal diagnosis:
Note: Bracketed numbers below refer to codes in the International Classification of Diseases (ICD-10-AM) chapters).
- Infectious and parasitic diseases (A00-B99), males/ females/ persons - Public/ All hospitals
- Total cancers (C00-D48), males/ females/ persons - Public/ All hospitals
- Mental health related conditions (F00-F99), males/ females/ persons - Public/ All hospitals
- Circulatory system diseases (I00-I99), males/ females/ persons - Public/ All hospitals
- Respiratory system diseases (J00-J99), males/ females/ persons - Public/ All hospitals
- Digestive system diseases (K00-K93), males/ females/ persons - Public/ All hospitals
- Musculoskeletal system and connective tissue diseases (M00-M99), males/ females/ persons - Public/ All hospitals
- Genitourinary system diseases (N00-N99), males/ females/ persons - Public/ All hospitals
- Pregnancy, childbirth and the puerperium (O00-O99), females - Public/ All hospitals
- Injury, poisoning and certain other consequences of external causes (S00-T98), males/ females/ persons - Public/ All hospitals
Note: Bracketed numbers below refer to codes in the International Classification of Diseases (ICD-10-AM)/ Australian Classification of Health Interventions (ACHI) for all procedures except hip fracture codes that are from the International Classification of Diseases (ICD-10-AM).
- Tonsillectomy (41789-00, 41787-01, 41786-01, 41789-01) - Public/ All hospitals
- Myringotomy, children aged 0 to 9 years (309) - Public/ All hospitals
- Hysterectomy, females aged 30 to 59 years (Procedure flag–Block , ; Codes 90450-00 , 90450-01  and 90450-02 ) - Public/ All hospitals
- Caesarean section, females aged 15 to 44 years (1340) - Public/ All hospitals
- Birth with an outcome of delivery, females aged 15 to 44 years- Public/ All hospitals
- Coronary artery bypass graft (672-679) - Public/ All hospitals
- Coronary angioplasty (669-671) - Public/ All hospitals
- Cardiac catheterisation (667-668) - Public/ All hospitals
- Hip fracture (M84.45, S72.00-S72.05, S72.08, S72.10-S72.11, S72.2) - Public/ All hospitals
- Knee replacement (1518-1519, 1523-1524) - Public/ All hospitals
- Knee arthroscopy (1501, 1503, 1505, 1517) - Public/ All hospitals
Confidentiality of data
Counts of less than ten admissions have been suppressed.
Data were not available for private hospitals in Tasmania, the Northern Territory or the Australian Capital Territory, to protect the confidentiality of the small number of private hospitals in these jurisdictions. As a result, where data are published for public and all hospitals, the 'all hospitals' data for these jurisdictions have also been confidentialised, as their publication would allow identification of the confidentialised private hospital data. The 'all hospitals' data in other jurisdictions have also been confidentialised where publication of public and all hospitals data would allow identification of private hospital data confidentialised due to small cell sizes. The decision was made to confidentialise the 'all hospitals' rather than the 'public hospitals' figure as admissions to public hospitals comprise the majority of admissions, both overall and from the most disadvantaged areas, and are those admissions for which the State and Territory Governments have priority responsibility for resourcing.
Note: Therefore remoteness/ quintile data for both private hospitals and all hospitals are also not published for these areas or for the whole of Australia.
Numerator: Admissions for the above categories
Admissions by hospital type and sex (excluding same-day admissions for renal dialysis): Total population, or total males/ females, where appropriate
Admissions by principal diagnosis: For pregnancy, childbirth and the puerperium, denominator is the number of females aged 15 to 44 years; for all other admissions, denominator is the total population
Admissions by procedure: For myringotomy, is children aged 0 to 9 years; for Hysterectomy, is females aged 30 to 59 years; for Caesarean section, is women aged 15 to 44 in hospital to give birth; for Birth with an outome of delivery, is women aged 15 to 44 years; and for all other admissions is the total population
Detail of analysis: Indirectly age-standardised rate per 100,000 (respective population); and/or indirectly age-standardised ratio, based on the Australian standard.
Source: Compiled by PHIDU using data from the Australian Institute of Health and Welfare, supplied on behalf of State and Territory health departments for 2012/13; and ABS Estimated Resident Population, average of 30 June 2012 and 2013.