NEW ZEALAND HEALTH INFORMATION SERVICE

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Scope

Purpose
The National Health Index (NHI) is the cornerstone of health information in New Zealand. It was established to provide a mechanism for uniquely identifying every healthcare user (HCU) by assigning each a unique number (known as the NHI number).

The purposes of the NHI include use:

• by health and disability support services to link health data pertaining to an individual to that individual to avoid mis-assignment of health and disability support information, for example, the wrong laboratory test results
• by health and disability support services to improve patient privacy protection when transferring an individual’s health data, for example, the receipt of laboratory test results by general practitioners
• by the Ministry of Health, in an encrypted form, so that data can be used for statistical purposes to report on the state of health of the New Zealand population, and to assist in the development of more effective services
• by health and disability support services to submit to, or access information from, the Medical Warnings System, for adverse drug warnings and other forms of medical alerts (see Medical Warnings System)
• by health and disability support services to identify previous health events, and the possible location of medical records through the Medical Warnings System.

Start date

The first national register was the National Master Patient Index, implemented in 1977. This was replaced with the NHI in 1993. Newborn babies have been registered on the national system since 1992. (See Collection methods below.)

Guide for use

Coverage is estimated to be 98 percent of the population.
When duplicate records for a healthcare user are identified, they are linked, one of their NHI numbers will be deemed to be the primary (or master), and the others become secondary NHI numbers. For the analysis of healthcare information relating to a unique individual, the primary NHI number should be used. Local systems may use secondary NHI numbers. For further details refer to the NHI Data Dictionary.

Collection methods – guide for providers

The main health sector data source is public hospitals. All local patient management systems have modules for identifying patients, so most systems are linked to the NHI. Where local patient index systems are in use, it is the responsibility of the local system management to ensure that local and national systems are synchronised.
In the primary healthcare sector, most registrations are via the NHI Helpdesk, a service run by the Ministry of Health. Some GPs have read-only access to the NHI.
New records for babies are submitted by hospitals and midwives. Infants are not to be registered on the NHI before their birth. The only exception to this is where tests on the fetus are carried out and need to be recorded for the future treatment needs of the infant. This practice should only occur in tertiary care facilities. NZHIS should be notified that this practice is occurring.
Fetal deaths (20 weeks gestation or more, and/or 400 grams birth weight) are registered on the NHI by NZHIS staff.

Frequency of updates

Ongoing. Real-time transactions.

Security of data

Access to the NHI is restricted to authorised users, and is permitted by the Health Information Privacy Code 1994 released under the Privacy Act 1993.
The NHI number is stored in encrypted form on other NZHIS systems.

Privacy issues

Use of the NHI number is restricted to authorised healthcare providers only as permitted by the Health Information Privacy Code 1994.

National reports and publications

None.

Data provision

None.



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