Volume 13, Number 2—February 2007
Research
Code-based Syndromic Surveillance for Influenzalike Illness by International Classification of Diseases, Ninth Revision
Nicola Marsden-Haug*1, Virginia B. Foster*, Philip L. Gould†, Eugene Elbert*2, Hailiang Wang*, and Julie A. Pavlin*3
Table 2
Data showing match of Air Force respiratory virus specimens to ICD-9 coded visits, January 2002–July 2003*
| Match day | No. specimens† |
|---|---|
| Did not match (removed from study) | 1,153 |
| Clinic day – 2 = specimen day | 47 |
| Clinic day – 1 = specimen day | 125 |
| Exact day match | 5,267 |
| Clinic day + 1 = specimen day | 680 |
| Clinic day + 2 = specimen day | 117 |
| Total | 7,389 |
*ICD-9, International Classification of Diseases, Ninth Revision.
†No. specimens obtained by day of matching visit.
