Application of Change Point Analysis to Time Series Data: The BioSense Experience

• Activity Number: 160
• Type: Topic Contributed
• Date/Time: Monday, August 2, 2010 : 10:30 AM to 12:20 PM
• Sponsor: Section on Statistics in Defense and National Security
• Author(s): Taha Kass-Hout*+ and Soyoun Park and Roy Xu and Paul McMurray and Howard Burkom
• Companies: CDC and SRA International and SRA International Inc. and CDC and The Johns Hopkins University
• Keywords: Biosurveillance ; BioSense ; Control Charts ; Change-Point Analysis ; Detection Algorithm ; Situation Awareness

Abstract

BioSense is an all-hazards surveillance program for achieving near real-time national public health situation awareness and early detection. Prospective anomaly detection methods such as the Modified EARS C2 are commonly adapted and used in BioSense and other public health syndromic surveillance systems. These methods however can produce an excessive false alert rate. Analyses results will be presented on the combined use of retrospective (e.g., Change Point Analysis (or CPA)) and prospective (e.g., C2) anomaly detection methods. This combined approach will help detect sudden aberrations in addition to subtle changes in local trends, help rule out alarm investigations, and assist with retrospective follow-ups. Examples on the utility of this combined approach applied to BioSense emergency departments' visits due to ILI, methods limitations and future work will be discussed at this talk.