Table 1. International Classification of Diseases, 9th Revision, Clinical Modification.

(ICD-9-CM) codes used to identify index visits

Condition	ICD-9-CM code
Non-specific upper respiratory infection	460, 464.%, 465.%, 466.1%
Acute bronchitis	466.0, 490
Acute rhinosinusitis	461.%
Acute pharyngitis	462, 463, 034.0
Acute otitis media	381.0%, 382.0%, 382.4, 382.9
Urinary tract infection	595.0, 595.4, 595.9, 599.0
Skin and soft tissue infection	681.%, 682.%, 683, 686.0%, 686.8%, 686.9
Pneumonia	481, 482.%, 483.%, 485, 486

% used to denote any potential numeric sequence