Canada Health Service Number

Detects Canada Health Service 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

medium

Confidence justification

Medium confidence: ten-digit numbers are common in many contexts. Corroborative evidence keywords such as 'health card' or 'OHIP' are needed for reliable detection. Context label evidence plus explicit template/example exclusion improves precision for high-risk identifiers. Added context gating and exclusion rules improve precision and reduce incidental matches.

Detection quality

Partial

Jurisdictions

ca

Regulations

FIPPA, Law 25 (QC), PHIPA, PIPEDA

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\d{10}\b

Corroborative evidence keywords

health card, health service, OHIP, health number, provincial health, carte santé, health card number, health identification, Manitoba Health, numéro de santé, patient number, personal health, PHIN, carte sante, health identification number, health insurance, health insurance number, health plan, health service number, health services (+43 more)

Proximity: 300 characters

Should match

• 1234567890 — Ten-digit health service number format
• 9876543210 — Ten-digit provincial health card number
• 5566778899 — Ten-digit health service identifier

Should not match

• 123456789 — Nine digits, too short for health service number
• 12345678901 — Eleven digits, exceeds health service format
• sample template placeholder number 123456789 — Template/sample context should be excluded even when numeric-like values appear
• 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

• Canada Health Service Number entity definition - Microsoft Learn