. 2004 Sep;10(9):1536–1543. doi: 10.3201/eid1009.030403

Table 2. Modified ICD-9 and ICD-9-CM definitions of deaths attributable to gastroenteritis of unknown etiology.

ICD-9	ICD-9-CM
Any death with an ICD-9 009.0, 009.2, or 558 code, excluding 1) radiation gastroenteritis deaths, identified by a 558 code plus the supplemental code for an abnormal reaction to a radiological procedure or therapy (E879.2)^a 2) toxic gastroenteritis deaths, identified by a 558 code plus any supplemental code for poisoning (909.0, 909.1, 960.0-989.9, E850.0-E869.9, E950.0-E950.9, E980.0-E980.9)^a 3) drug-induced diarrhea deaths, identified by a 558 code plus any supplemental code for an adverse drug reaction (E930.0-E949.9), or by a 009.0 or 009.2 code plus any supplemental code for an adverse reaction to an antibiotic (E930.0-E931.0)^a	Any death with an ICD-9-CM 009.0-009.3, 558.9, or 787.91 code, excluding 1) drug-induced diarrhea deaths, identified by a 558.9 or 787.91 code plus any supplemental code for an adverse drug reaction (E930.0-E949.9), or else by a 009.0-009.3 code plus any supplemental code for an adverse reaction to an antibiotic (E930.0-E931.0)^b

ICD-9

ICD-9-CM

Any death with an ICD-9 009.0, 009.2, or 558 code, excluding 1) radiation gastroenteritis deaths, identified by a 558 code plus the supplemental code for an abnormal reaction to a radiological procedure or therapy (E879.2)^a 2) toxic gastroenteritis deaths, identified by a 558 code plus any supplemental code for poisoning (909.0, 909.1, 960.0-989.9, E850.0-E869.9, E950.0-E950.9, E980.0-E980.9)^a 3) drug-induced diarrhea deaths, identified by a 558 code plus any supplemental code for an adverse drug reaction (E930.0-E949.9), or by a 009.0 or 009.2 code plus any supplemental code for an adverse reaction to an antibiotic (E930.0-E931.0)^a

Any death with an ICD-9-CM 009.0-009.3, 558.9, or 787.91 code, excluding 1) drug-induced diarrhea deaths, identified by a 558.9 or 787.91 code plus any supplemental code for an adverse drug reaction (E930.0-E949.9), or else by a 009.0-009.3 code plus any supplemental code for an adverse reaction to an antibiotic (E930.0-E931.0)^b

^aThe supplemental code must be listed on the same line or one line after the code for gastroenteritis of unknown etiology on part I of the death certificate (for conditions resulting in death), or else both codes must be listed together on part II of the death certificate (for other contributing conditions). ^bSupplemental codes on NHDS files are not explicitly associated with other diagnoses. Therefore, gastroenteritis of unknown etiology was assumed to be drug-induced if any other diagnosis was one of the specified adverse drug reactions.