description: |-
  Patient's "public" ID, as used and shown on the GPIS patient page. Not necessarily unique,
  and not necessarily present; 0 indicates no patid is known or this GPIS does not use (numeric)
  public IDs.
  
  The primary purpose of this field is to show it to medical professionals working at this practice
  who can use it to search for this dossier and is a way to communicate without sharing privacy-sensitive
  details.
  
  The number is guaranteed to be positive, and have at most 14 digits. We suggest using a 64-bit numeric
  type to store the number; transferring this number via IEEE-double math (common, in JSON) is safe, as
  the number will not exceed the range within which all whole integers are perfectly representable (~`2^52`).
type: integer
format: int64
example: 1234