NEW ZEALAND HEALTH INFORMATION SERVICE

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The purpose of the National Health Index (NHI), including the National Health Index number (NHI number), is to help with the planning, co-ordination and provision of health and disability support services across New Zealand.

The purpose of the Medical Warnings System (MWS) is to warn health and disability support services of any known risk factors that may be important when making clinical decisions about individual patient care.

Unique identification

The NHI number is the unique identifier for all patients in public hospitals and is the cornerstone of patient-related transactions within the hospital, both clinical and administrative. Very rarely do hospitals rely on names alone for identifying patients.

The NHI number identifies the patient for referrals, visits to the hospital, tests, and patient-related correspondence. Correct identification of the patient is a critical aspect of clinical safety.

Linking information

The NHI number ties together all patient documentation and internal patient systems in hospitals. The NHI number is on patient labels, which are used on most items of patient documentation, from pharmaceutical labels to discharge summaries. Usually, the hospital’s central patient management system, which manages admissions, discharges, and transfers of patients, is linked to other clinical systems such as laboratory, pharmacy, dental and surgical booking by means of the NHI number.

Where regional services exist, such as centralised diagnostic services, health and disability support services may receive the diagnostic results electronically from an external source. The NHI number is used to ensure that the results are associated with the correct patient.

Communication

The NHI number is used:

• for communication with patients, for example, when advising patients about an outpatient appointment or an inpatient booking
• to report patient events to national data collections, such as those held by the National Testing Centre, the Centre for Adverse Reactions Monitoring and the Ministry of Health
• for communications with other health professionals relating to patients, for example when a patient is:
• referred to a hospital
• referred or transferred to another specialist within the hospital
• referred or transferred to another hospital
• discharged from the hospital
• discharged to another healthcare facility, such as a rest home.

The NHI number is used to:

• obtain information from the hospital’s internal systems, by allowing online access to information such as diagnostic results, previous clinical events, or planned future events such as elective surgical bookings
• access information from the MWS, such as medical warnings, medical alerts, and previous secondary care events
• access information from the National Immunisation Register, such as immunisation status.

The NHI number is used by:

• the hospital’s community health service, to co-ordinate and manage its visits (for example, for community health nursing or mental health contacts)
• screening programmes, to co-ordinate and manage the programme; this includes tracking and contacting clients and potential clients, and managing clinical information
• public health units, to co-ordinate and manage patient-based public health services such as immunisation and school dental services.

The NHI number is used to uniquely identify health and disability support information in national clinical databases that are accessible to approved health and disability support services. There are two databases:

• Medical Warnings System. The MWS is designed to warn health and disability support services of any known risk factors that may be important when making clinical decisions about individual patient care. This data can be accessed only through the NHI.
• National Immunisation Register. The NIR is designed to assist vaccinators to increase New Zealand’s immunisation coverage through timely access to immunisation histories.

The Ministry of Health uses a coded form of the NHI number to uniquely identify health and disability support events on statistical databases. The databases are used to:

• produce statistical publications
• meet international reporting requirements
• assist with developing policy
• facilitate research
• support the planning of health and disability support services, including health needs assessment
• assist with monitoring the performance of health and disability support services.

An encrypted form of the NHI number is used in statistical databases to help protect the privacy of individuals while enabling data from different places to be linked.

Auditing

Primary Health Organisations (PHOs) are funded on a capitation basis (the amount paid is determined by the number of patients). Each quarter, the PHO provides the Ministry of Health with a copy of its patient register, including NHI numbers, which the Ministry uses to calculate the subsidy payment to the PHO. NHI numbers are used to ensure patient registers are accurate for funding purposes (for example, to prevent double payments to one PHO for the same person or payments to more than one PHO for the same person).

When claiming for a patient ‘fee-for-service’ subsidy, general practitioners should forward the NHI number of the patient to the Ministry of Health. This information is used for audit purposes and to adjust payments for capitation practices by deducting any payment that has already been made to a PHO for the care of that patient.

When claiming for a patient subsidy, laboratories and pharmacies should forward to the Ministry of Health the NHI number and associated event information (which details what test was undertaken or what pharmaceutical was dispensed). This information is used for auditing purposes and to create statistical databases of, for instance, pharmaceutical dispensings.

Anonymity

The NHI number may also be used as an anonymous reference to the patient in research undertaken by the hospital.