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Tools/SIT X-Ray/U.K. National Health Service Number

U.K. National Health Service Number

live testingcurated1 patternproximity 300recommended confidence 85 (high)

Ten digits in 3-3-4 format validated with the NHS modulus 11 check digit algorithm.

High confidence only, and it requires either an NHS keyword or a date-of-birth keyword (GP, DOB) in proximity. The check digit means random 10-digit numbers rarely match, but valid NHS numbers without nearby context never match at all.

The patterns, as the engine reads them

confidence 85 (high)
  • Primary: Func_uk_nhs_number: Ten digits in 3-3-4 format validated with the NHS modulus 11 check digit.
  • Any of these:
    • Keyword_uk_nhs_number: 8 keywords (word match), e.g. "health services authority", "health authority", "national health service"
    • Keyword_uk_nhs_number_dob: 5 keywords (word match), e.g. "GP", "DOB", "D.O.B"
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