Practical HL7 v2
Short, practical articles on the problems interface analysts and data teams run into with HL7 v2 feeds.
What is HL7? A practical introduction to HL7 v2 messages
A plain-English tour of HL7 version 2: who uses it, how a message is put together, how to read one field by field, and how messages travel between systems.
ADT^A08 vs ADT^A31: patient updates vs person updates
Both events update demographics, but one belongs to a visit and the other to the person. Mixing them up creates phantom encounters and missed updates.
Finding HIV, substance use and other sensitive data in HL7 feeds
Sensitive information rarely sits in one tidy field. It turns up in diagnosis codes, free-text notes, lab results and medication names. Here's where to look, and how to find it reliably.
HL7 v2 escape sequences explained: \F\, \S\, \T\, \R\, \E\ and more
Why \F\ and \.br\ show up in HL7 messages, what each escape sequence means, and the common mistakes that quietly split or truncate fields.
How to tell which HL7 v2 version a message really is
MSH-12 says which version a message follows, but it's often wrong. Here's how to read the real version from the message itself.