Reference
The HL7 v2 and X12 EDI Reference Every Healthcare Testing Team Needs
Field-by-field breakdowns of the segments you actually touch day to day — what each one means, its valid values, a synthetic example, and the testing mistake it's most associated with.
HL7 v2 15 fields
PID Segment → HL7 v2 15 fields
PV1 Segment →