LOINC_NUMS without checksum didgit

Hi, release 2.70 has 12 LOINC_NUMs without checksum digits (that is, the ids fail the checksum check). Is this intended?

LOINC_NUM Component

44478 Amdinocillin

44507 Amikacin

44535 Amikacin

44204 Acyclovir

44233 Almecillin

44259 Almecillin

44288 Almecillin

44325 Almecillin

44354 Amantadine

44382 Amdinocillin

44411 Amdinocillin

44440 Amdinocillin



Hi Emily,

We just completed the uptake of content at 3M and didn’t encounter this issue. The theory of issuing terms without the Mod10 check digit is still adhered to. I’ve got the LoincTableCore open and filtering on either component or the beginning of a LOINC term.

I suspect there is a corruption or format issue with the download at your facility. Will you have someone investigate? The 444** numbers listed for Amdinocillin in your email are for other chemistries.

Thank you,


I will check and get back to you. Thank you.



These look to be the 12 LOINC codes where Excel interprets the values as dates. If you open Loinc.csv in Excel, it will try to be helpful and convert the codes to a date, e.g. 1-8, 2-6, 3-4. The 12 can be found using this SearchLOINC query (LOINC login required):


I am looking in LOINC.csv for 2.70 and I see these bad identifiers. Check line 1001 of the file for an example. I will re download the file.

Thank you.


Thank you, Tim, it was the date conversion problem; it is fixed.

I really appreciate the rapid reply.