Table 2. ICD-9 study codes used for staphylococcal toxic shock syndrome case ascertainment*.

Code	Associated diagnosis
Specific toxic shock syndrome code
040.89 or 040.82†	Toxic shock syndrome
Nonspecific toxic shock syndrome codes
038.11	Staphylococcus aureus septicemia
038.19‡	Other staphylococcal septicemia
038.9	Unspecified sepsis
785.50	Shock without mention of trauma
785.59 or 785.52†	Sepsis

*ICD-9, International Classification of Diseases, 9th Revision.
†The code assigned to toxic shock syndrome changed from 040.89 to 040.82 on October 1, 2002, and the code assigned to sepsis changed from 785.59 to 785.52 on October 1, 2003. Although the codes changed, their associated diagnoses remained unchanged and are considered mutually exclusive.
‡Code eliminated after interim analysis of 627 medical records at 14 of 24 hospitals. Of 122 records receiving only this code, 40% had 0 case criteria, all had <3 criteria, and 88% had bacteremia with a staphylococcal species other than S. aureus.