NEW ZEALAND HEALTH INFORMATION SERVICE

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The National Health Index (NHI) and the Medical Warnings System (MWS) are separate systems, which are both managed by the New Zealand Health Information Service (NZHIS). The MWS can be accessed through the NHI, but access to data on the MWS is restricted solely to health and disability support services for use in caring for the individual.

Data dictionaries detailing data elements that comprise the NHI and MWS are available here.

National Health Index

The National Health Index number (NHI number) is a unique number that is assigned to each person using health and disability support services. The NHI is an index of information associated with that unique number. The Health Information Privacy Code 1994 places restrictions on the creation and use of unique identifiers such as the NHI number.

The NHI holds the following information: name (including alternative names such as maiden names), NHI number, address, date of birth, sex, New Zealand resident status, ethnicity; date of death, and flags indicating any medical warnings or donor information. Clinical information is not recorded on the NHI.

Thus, individuals can be positively and uniquely identified for the purposes of treatment and care, and for maintaining medical records. This means that healthcare providers can be sure that they are talking about the same person, thereby reducing the chance of making a clinical decision based on wrong information. This certainty is increasingly important as patients become more mobile, when care occurs in both the primary and secondary sectors, and where emphasis is on ‘shared’ care.

The NHI and the NHI number are central to the vision of safe and secure sharing of information among health and disability support services. An NHI number is fundamental for services to link information and get a better understanding of each person’s needs.

The complexity of hospital care has led to the development of independent clinical information systems, such as pharmacy, laboratory, and admission/discharge/transfer. Important information relating to an individual patient is often held in more than one place. The NHI number allows all this information to be brought together.

A detailed account of how the NHI number can be used is available here.

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. The MWS allows data from other sources to be available where it could be important. It is not designed to be a replacement for a service’s own clinical information system.

The MWS contains the following:

• Medical warnings. These warn the provider of any known dangers relating to the specific individual and the administration of therapeutic medicines (for example, allergies, drug sensitivities, or adverse medical reactions). Warnings are categorised as ‘warnings’ or ‘dangers’. Doctors submit an incident, such as an allergic reaction, as a warning. The Centre for Adverse Reactions Monitoring can review and upgrade this warning to a danger if it could be potentially life-threatening.
• Medical alerts. These indicate significant medical conditions, such as renal failure requiring dialysis, which are likely to have an impact on care decisions.
• Healthcare event summaries. These are derived from event reports to the National Minimum Dataset and are therefore restricted to hospital events. The summary includes the hospital you were in, the dates you were in hospital, and the principal diagnosis causing admission to hospital. There is a field in the National Minimum Dataset that can prevent a summary from passing to the MWS when absolute confidentiality is required.
• Contact details. Next of kin or other contacts whom the patient wishes to be notified in an emergency can be recorded here.
• Donor information. A person’s wishes regarding organ donation can be recorded here.

Like the NHI, the MWS contains information of operational-level significance, and the responsibility for maintaining the content of the MWS rests with health and disability support services.

The MWS enables important data from different clinical information systems to be available to these services where and when it could be important.

A detailed account of how the MWS can be used is available here.