Standard classification systems
The standard classification systems used in the health and disability system are:
- 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)
- ICD-O – International Classification of Diseases for Oncology.
New Zealand upgraded concurrently with Australia to ICD-10-AM/ACHI/ACS Eleventh Edition on 1 July 2019.
ICD-11 is in development and will replace ICD-10-AM when it is introduced within the next few years.
A National Cancer Information Work Programme was established in 2003 by the then New Zealand Health Information Service (NZHIS) to improve the completeness, quality, accuracy and currency of data held on the New Zealand Cancer Registry and associated feeder sources such as the Mortality Collection.
As a component of this programme, HISO endorsed ICD-10 AM and ICD-O as national coding standards, allowing for consistent coding of clinical and cancer data. ICD classifications were already de facto standards, used by the health and disability sector for more than 30 years.
These standards are an essential building block for any national data set coding clinical and cancer data in New Zealand and used for statistical and administrative purposes.
The benefits of having standardised coding include an enhanced ability of sector and health researchers to more quickly identify trends in the incidence of disease, mortality and survival.
The ICD standards complement SNOMED CT, the international terminology standard for the descriptive and interoperable health and disability information used in patient care.
The World Health Organization (WHO) produces new editions of ICD approximately every ten years and the National Centre for Classification in Health (NCCH) has produced an Australian Modified (AM) version about every two years.
The ongoing maintenance of these classifications is performed by WHO and NCCH and monitored by the Ministry of Health.