Metathesaurus Additional Entry Terms for ICD-9-CM (MTHICD9) are produced by the U.S. National Library of Medicine (NLM) and are based on entry terms found in the ICD-9-CM tabular data.
MTHICD9 represents Metathesaurus entry terms created for ICD-9-CM codes. They were created by NLM to provide additional synonyms and entry terms for ICD-9-CM codes.
For more information about ICD-9-CM, see the ICD-9-CM source synopsis.
MTHICD9 provides additional synonyms and closely-related names extracted from the ICD-9-CM tabular lists for diseases, procedures, and supplementary classifications.
Metathesaurus Update Frequency
MTHICD9 is updated annually in the November Metathesaurus release, in conjunction with ICD-9-CM.