Abstract
In Los Angeles County, emergency department data is collected from hospitals and classified into syndromes based on chief complaints. To validate this respiratory syndromic surveillance categorization, chief complaint data were compared to discharge diagnoses extracted from electronic health records from one hospital emergency department in Los Angeles County during one week in January 2013. The agreement between syndrome classification and discharge diagnosis for respiratory reports is high (k=0.75), though over 25% of diagnosis data were missing. Further validation of additional syndromes is needed. Electronic health records are valuable sources of data and can enhance the validity of syndromic surveillance systems.