Morbidity Analysis SECTION
3.2 C ODING OF D IAGNOSES AND P ROCEDURES
Coding of HIPE hospital activity is performed by the HIPE Clinical Coder who
translates medical terminology into code; the Coder performs an essential function in providing high quality, accurate, standardised medical information. The source document for coding for the HIPE system is the medical record or chart. Documentation within the medical record includes the discharge summary or letter, nursing notes, consultation reports, progress notes, operative reports, pre- and post- operative reports, and pathology reports. The Coder uses the whole chart to extract the diagnoses and procedures that are critical to representing the essential features of the patient and their hospital stay in accordance with international and national coding standards. Appendix III contains the HIPE Data Entry Form for 2012, which
details the information coded for each hospital discharge. No interpretation of test
results may be presumed by the Coder and all diagnoses recorded must be
documented by a clinician in the chart.3
Discharges are coded using the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, Australian Modification (ICD-10-AM), Australian Classification of Health interventions (ACHI), Australian Coding Standards (ACS), 6th Edition and Irish Coding Standards (ICS).4, 5, 6,7, 8 Details of the diagnosis
and procedure coding scheme are provided in Tables 3.1 and 3.2. ACS are developed to provide guidance in the application of ICD-10-AM and ACHI codes. Standards are categorised by site and or body system according to the clinical specialty to which a disease or procedure relates. ICS apply to activity coded in HIPE and provide guidance and instruction on all aspects of HIPE data collection by addressing issues relevant to the Irish hospital system. ICS are developed to complement the ACS and are revised regularly to reflect changing clinical practice.
3 The Health Research and Information Division (HRID) of the ESRI is responsible for training coders. For further information
see www.hipe.ie
4 For further information on the selection of ICD-10-AM as the clinical coding scheme for Ireland, see Murphy, D., Wiley,
MM., Clifton, A., McDonagh, D., 2004, Updating Clinical Coding in Ireland: Options and Opportunities. Dublin: The
Economic and Social Research Institute.
5 National Centre for Classification in Health (NCCH), 2008: The International Statistical Classification of Diseases and
Related Health Problems, Tenth Revision, Australian Modification (6th Ed): NCCH, Faculty of Health Sciences, The University of Sydney.
6 The spelling conventions of ICD-10-AM comply with the Macquarie Dictionary, as recommended by the Australian
government style manual.
7 Ireland changed from ICD-10-AM 4th Edition to ICD-10-AM 6th Edition in 2009. For further information on changes in
coding, see previous HIPE national reports, available at www.hipe.ie
8 Irish Coding Standards provide guidelines for the collection of HIPE data for all discharges and are to be used in
conjunction with 6th Edition ICD-10-AM/ACHI/ACS and the relevant HIPE Instruction Manual. For further information, see
Table 3.1 provides details of the structure of ICD-10-AM Diagnosis Codes and presents the chapter structure of ICD-10-AM diagnosis codes.
TABLE 3.1 ICD-10-AM Diagnosis Codes, Chapter and Title
ICD-10-AM Diagnosis Codes
The 'core' disease classification of ICD-10-AM is the three character code, which is the mandatory level of coding for international reporting to the World Health Organization (WHO) for general international comparisons. This core set of codes has been expanded to four and five character codes so that important specific disease entities can be identified, while also maintaining the ability to present data in broad groups to enable useful and understandable information to be obtained. The ICD-10-AM is a variable-axis classification. Its structure is designed principally to facilitate epidemiological analysis. Diseases are organised in the following groups: epidemic diseases; constitutional or general diseases; local disease arranged by site; developmental diseases; and injuries.
Most of the tabular is taken up with the main disease classification composed of 22 chapters. The first character of the ICD- 10-AM code is a letter, and each letter is associated with a particular chapter, except for the letter D, which spans both Chapter 2 Neoplasms and Chapter 3 Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism, and the letter H, which is used in both Chapter 7 Diseases of the eye and adnexa and Chapter 8 Diseases of the ear and mastoid process. Four chapters (Chapters 1, 2, 19 and 20) use more than one letter in the first position of their codes.
WHO intends the codes U00–U99 to be used for provisional assignment of new diseases of uncertain aetiology and for specific research purposes. U50–U71 are used in ICD-10-AM to classify sporting activities previously classified to Y93.0 Activity, While engaged in sports.
Chapter and Title Code Prefix Chapter and Title Code Prefix 1 Certain infectious and parasitic
diseases A, B 12 Diseases of the skin and subcutaneous tissue L 2 Neoplasms C, D 13 Diseases of the musculoskeletal system and
connective tissue M
3 Diseases of the blood and blood- forming organs and certain disorders involving the immune mechanism
D 14 Diseases of the genitourinary system N 4 Endocrine, nutritional and metabolic
diseases E 15 Pregnancy, childbirth and the puerperium O 5 Mental and behavioural disorders F 16 Certain conditions originating in the
perinatal period P
6 Diseases of the nervous system G 17 Congenital malformations, deformations and chromosomal abnormalities Q 7 Diseases of the eye and adnexa H 18 Symptoms, signs and abnormal clinical and
laboratory findings, not elsewhere classified R 8 Diseases of the ear and mastoid
process H 19 Injury, poisoning and certain other consequences of external causes S, T 9 Diseases of the circulatory system I 20 External causes of morbidity and mortality U, V,
W, X, Y 10 Diseases of the respiratory system J 21 Factors influencing health status and
contact with health services Z 11 Diseases of the digestive system K 22 Codes for special purposes U
Source: National Centre for Classification in Health (NCCH), 2008: The International Statistical Classification of Diseases and Related Health
Problems, Tenth Revision, Australian Modification (6th Ed): Australian Coding Standards. Sydney: NCCH, Faculty of Health Sciences,
Table 3.2 provides details of the structure of ACHI Procedure Codes and presents the chapter structure for these ACHI procedure codes.
TABLE 3.2 Australian Classification of Health Interventions (ACHI), Chapter and Title
Australian Classification of Health Interventions (ACHI)
The Australian Classification of Health Interventions (ACHI) was developed by the NCCH and is generally based on the Commonwealth Medicare Benefits Schedule (MBS).
The main features of the classification are:
1) The procedure classification captures procedures and interventions performed in public and private hospitals, day centres and ambulatory settings. Allied health interventions, dental services and procedures performed outside the operating theatre are included.9
2) The procedure classification is based on the Commonwealth Medicare Benefits Schedule (MBS) and consists of a seven character code in the format xxxxx-xx. Generally, the first five characters represent the MBS item number. A two character extension number has been attached to each MBS item number to represent individual procedural concepts (e.g., 36564-00). The two character extensions are also used in anaesthetic procedure codes to indicate ASA, while in pharmacotherapy they are used to indicate drug type.
Other ACHI interventions which are not represented in MBS are allocated a code number from the 90000 series. Note: 97000 codes are reserved for dental services.
3) The structure of the procedure classification is based on anatomy rather than surgical specialty. Chapters closely follow the chapter headings of the WHO ICD-10 to maintain parity with the disease classification.
4) Nonsurgical procedures are listed separately from the surgical procedures, whenever feasible.
5) A hierarchical structure with the following axes:
• First level – anatomical site axis
• Second level – procedure type axis
• Third level – block axis
6) Inclusion of many more procedures which can be utilised in non-institutional settings, such as community based health and ambulatory care.
Chapter and Title Chapter and Title
1 Procedures on nervous system 11 Procedures on urinary system 2 Procedures on endocrine system 12 Procedures on male genital organs 3 Procedures on eye and adnexa 13 Gynaecological procedures 4 Procedures on ear and mastoid process 14 Obstetric procedures
5 Procedures on nose, mouth and pharynx 15 Procedures on musculoskeletal system 6 Dental services 16 Dermatological and plastic procedures 7 Procedures on respiratory system 17 Procedures on breast
8 Procedures on cardiovascular system 18 Radiation oncology procedures
9 Procedures on blood and blood-forming organs 19 Non-invasive, cognitive and other interventions, not elsewhere classified
10 Procedures on digestive system 20 Imaging services
Sources: National Centre for Classification in Health (NCCH), 2008: The International Statistical Classification of Diseases and Related Health
Problems, Tenth Revision, Australian Modification (6th Ed): Australian Coding Standards. Sydney: NCCH, Faculty of Health Sciences,
The University of Sydney. p. 3.
National Centre for Classification in Health (NCCH), 2008: The Australian Classification of Health Interventions (ACHI) Tabular List of
Interventions. Sydney: NCCH, Faculty of Health Sciences, The University of Sydney. p. iii.
3.2.1 Definition of a Diagnosis
In 2012, HIPE collected a principal diagnosis for each discharge, together with up to 29 additional diagnosis codes.