New Zealand Ministry of Health Number

Detects New Zealand Ministry of Health Number patterns. This pattern is based on a Microsoft Purview built-in sensitive information type. Due to the generic numeric format, corroborative evidence keywords are essential for reliable detection.

Type

regex

Engine

universal

Confidence

high

Confidence justification

High confidence: the three-letter-four-digit format is relatively distinctive. Combined with NHI-related keywords, this pattern reliably identifies New Zealand Ministry of Health numbers. Added context gating and exclusion rules improve precision and reduce incidental matches.

Detection quality

Verified

Jurisdictions

nz

Regulations

Privacy Act 2020 (NZ)

Frameworks

ISO 27001, ISO 27701, SOC 2

Data categories

phi, health, government-id

Scope

narrow

Risk rating

8

Platform compatibility

Purview: Compatible, GCP DLP: Compatible, Macie: Compatible, Zscaler: Compatible, Palo Alto: Compatible, Netskope: Compatible

Pattern

\b[A-Z]{3}\d{4}\b

Corroborative evidence keywords

NHI, national health index, ministry of health, health number, NHI number, health identifier, health index number, health practitioner index, health service, medical record number, patient identifier, patient number, field, column, row, entry, record, value, form, register (+21 more)

Proximity: 300 characters

Should match

• ZZZ1234 — Standard NHI number format with three letters and four digits
• ABC5678 — NHI number with uppercase letters and digits
• XYZ9012 — NHI format identifier

Should not match

• ZZ1234 — Only two letters, too short for NHI format
• ABCD5678 — Four letters, exceeds NHI letter prefix length
• template example placeholder record identifier — Template/sample context should be excluded even when anchor words are present

Known false positives

• Generic numeric sequences matching the digit pattern in non-health contexts Mitigation: Require corroborative evidence keywords within the proximity window to distinguish health identifiers from general numeric data.
• Reference numbers or account identifiers from other domains with similar digit counts Mitigation: Layer with document classification to prioritise matches in health and medical documents.

References

• New Zealand Ministry of Health Number entity definition - Microsoft Learn