The Myths and Truths About Comparing Syndromic Data Across Sites

One of the more recent successes of NSSP has been the introduction of more robust data quality monitoring and reporting. However, despite the increased insight into data quality, there are still concerns about data sharing and comparisons across sites. For NSSP to be most effective, users need to feel confident in sharing data and making comparisons across sites.


January 19, 2018

Comparing and Contrasting Two ESSENCE Syndrome Definition Query Methods

The Kansas Syndromic Surveillance Program (KSSP) utilizes the ESSENCE v.1.20 program provided by the National Syndromic Surveillance Program to view and analyze Kansas Emergency Department (ED) data. Methods that allow an ESSENCE user to query both the Discharge Diagnosis (DD) and Chief Complaint (CC) fields simultaneously allow for more specific and accurate syndromic surveillance definitions. As ESSENCE use increases, two common methodologies have been developed for querying the data in this way.

January 25, 2018

An Evaluation of Heat-Related Emergency Department Visits Based on Differences in Heat Syndrome Definitions in Northern Illinois

Comparison of heat-related health effects across regions or among different syndromic surveillance systems is problematic due to the lack of a standardized heat-related syndrome definition. While a national standard for common heat-related syndromes would facilitate data comparisons, local customization of syndromes to adjust for unique public health events or characteristics is often necessary to optimize use of syndromic surveillance data.


August 22, 2018

The Epidemiologic Vocabulary of the West and the Former Soviet Union: Different Sides of the Same Science

As part of the US Department of Defense strategy to counter biological threats, the Defense Threat Reduction Agency’s Cooperative Biological Engagement Program is enhancing the capabilities of countries in the former Soviet Union (FSU) to detect, diagnose, and report endemic and epidemic, man-made or natural cases of especially dangerous pathogens. During these engagements, it was noted that Western-trained and Soviet-trained epidemiologists have difficulty, beyond that of simple translation, in exchanging ideas.

June 25, 2018

Comparison of respiratory, febrile and influenza-like illness syndromes to detect laboratory-reported H1N1 and RSV, Influenza Season 2009–10, New York City

The New York City (NYC) Department of Health and Mental Hygiene monitors visits daily from 49 of 54 NYC emergency departments (EDs), capturing 95% of all ED visits. ED visits for influenza-like illness (ILI) have reflected influenza activity in NYC, better than the more broadly defined fever/flu and respiratory syndromes, but the correlation with H1N1 is unknown. 

Laboratory-confirmed influenza and respiratory syncytial virus (RSV) were made reportable in NYC in February 2008. DOHMH receives electronic reports of positive tests. 

June 14, 2019

Comparison of the US outpatient influenza-like illness surveillance network and the Google Flu Trends from 2008 to 2010 developed a regression model that used the volume of influenza-related search queries best correlated with the proportion of outpatient visits related to influenza-like illness (ILI) model to estimate the level of ILI activity. For calibration, the model used ILINet data from October 2003 to 2009, which report weekly ILI activity as the percentage of patient visits to health care providers for ILI from the total number patient visits for the week. Estimates of ILI in 121 cities were added in January 2010.


June 14, 2019

Detection of multiple overlapping anomalous clusters in categorical data

Syndromic surveillance typically involves collecting time-stamped transactional data, such as patient triage or examination records or pharmacy sales. Such records usually span multiple categorical features, such as location, age group, gender, symptoms, chief complaints, drug category and so on. The key analytic objective to identify potential disease clusters in such data observed recently (for example during last one week) as compared with baseline (for example derived from data observed over previous few months).

June 14, 2019

Effect of expanded recommendations for pediatric seasonal influenza vaccination: an international comparison

Seasonal influenza epidemics are responsible for over 200,000 hospitalizations in the United States per year, and 39,000 of them are in children. In the United States, the Advisory Committee on Immunization Practices guides immunization practices, including influenza vaccination, with recommendations revised on an annual basis. For the 2006–2007 flu season, the Advisory Committee on Immunization Practices recommendations for influenza vaccination began including healthy children aged 24–59 months (two to four years), a shift that added 10.6 million children to the target group.

June 17, 2019

Emergency department diagnosis code data for surveillance of vaccine adverse events: comparison with the national vaccine adverse event reporting system

Nationally, vaccine safety is monitored through several systems including Vaccine Adverse Event Reporting System (VAERS), a passive reporting system designed to detect potential vaccine safety concerns. Healthcare providers are encouraged to report adverse events after vaccination to VAERS, whether or not they believe that the vaccine caused the adverse event. The 2009 Pandemic H1N1 influenza vaccine became available in the United States in October 2009.

June 17, 2019

Evaluating the performance of two alternative geographic surveillance schemes

Influenza-like illness (ILI) data is collected by an Influenza Sentinel Provider Surveillance Network at the state (Iowa, USA) level. Historically, the Iowa Department of Public Health has maintained 19 different influenza sentinel surveillance sites.

June 17, 2019


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