2014.ISDS.Abstracts.Final.pdf


ISDS Annual Conference Proceedings 2014. This is an Open Access article distributed under the terms of the Creative Commons Attribution-
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ISDS 2014 Conference Abstracts

Impact of Patient Self-Registration in Emergency 
Departments on Syndromic Surveillance Data

Melinda C. Thomas*, David Atrubin and Janet J. Hamilton

Florida Department of Health, Tallahassee, FL, USA

Objective
To assess the effect of patient self-registration methods in hospital 

emergency departments on data in a syndromic surveillance (SS) 
system and provide suggestions for analysis of these data.

Introduction
The Florida Department of Health electronically receives hospital 

emergency department (ED) data from 180 EDs located in 54 of 
its 67 counties through its Electronic Surveillance System for the 
Early Notification of Community-based Epidemics (ESSENCE-FL). 
Florida EDs have begun to offer self-registration options to patients, 
which include ED self check-in kiosks, and pre-visit registration 
smartphone applications and websites. ESSENCE-FL receives ED 
data from multiple hospitals that use these patient self-registration 
methods. To date, limited investigation has been carried out to 
determine the impact of these self-registration methods on the data 
submitted to ESSENCE-FL. This project investigates and describes 
how SS data are affected by these options and provides possible best 
practices for identifying and analyzing these data.

Methods
The ESSENCE-FL system was queried by hospital with a weekly 

time resolution for chief complaints (CCs) containing the term “I” for 
the period of Week 1, 2006 to Week 31, 2014. This query assessed 
the CCs of visits for all hospitals reporting to ESSENCE-FL to 
target potential patient-entered CCs. Hospitals with a dramatic and 
sustained increase of visits with “I” in the CC over the time period 
were identified as hospitals of interest that may be using patient self-
registration. CC and discharge diagnosis (DD) data were analyzed 
for each hospital of interest to investigate potential disparities in the 
data for the time periods before and after implementation of self-
registration, including changes to ED visits flagged by the system 
as Visits of Interest (VOI) and to visits binned in the influenza-like 
illness (ILI) syndrome category. ED visits are binned in the VOI 
category when a term of epidemiological significance is found in the 
concatenated CC-DD field. Efforts were made to contact hospitals 
to confirm their use of self-registration methods. The results for one 
hospital using the iNotify by iTriage smartphone application and 
website are given below.

Results
Data from one of the 16 hospitals of interest were compared for 

time periods before and after the estimated date the hospital ED 
implemented the iNotify self-registration feature. During the period 
before implementation (Week 1, 2007 to Week 8, 2011), 0.60% of 
all ED visit CCs contained the term “I” (median 2 visits per week, 
range 0-12). During the period after implementation (Week 9, 2011 
to Week 31, 2014), 1.18% of all ED visit CCs contained the term “I” 
(median 4 visits per week, range 0-31). For ED visits binned in the 
ILI Syndrome category, 0.76% of ED visit CCs contained the term 
“I” before implementation compared to 0.89% of ED visit CCs after 
implementation. There was a negligible difference in ED visits in the 
VOI category when comparing the before and after implementation 
periods (0.20% vs. 0.23%, respectively). A qualitative analysis of the 

CC field before and after implementation of patient self-registration 
will also be discussed.

Conclusions
Preliminary analysis indicates that, although not exhaustive, the 

simple query used to find increases in visits with CCs containing “I” 
proved a sufficient method to find hospitals potentially using patient 
self-registration methods with minimal resource investment. There is a 
discernable difference in the use of CC terms after the implementation 
of a patient self-registration method, but the change does not appear 
to negatively affect the ability to successfully query the data for 
VOI. How a hospital decides to store and use the patient self-entered 
responses directly impacts the content of the CC data submitted to 
a SS system. Understanding the internal business processes of a 
hospital is essential to providing context for the data received in a 
SS system, which sometimes necessitates communication with the 
hospital. Implementing a rigorous data field documentation process 
for each hospital submitting data to a SS system could greatly ease 
the burden of both hospital and public health staff in performing such 
data field investigations and analyses in the future.

Keywords
ESSENCE-FL; Emergency department data; Patient self-registration; 
Syndromic surveillance

Acknowledgments

Johns Hopkins University Applied Physics Laboratory
Applied Public Health Informatics Fellowship Program

*Melinda C. Thomas

E-mail: melinda.thomas2@flhealth.gov    

Online Journal of Public Health Informatics * ISSN 1947-2579 * http://ojphi.org * (1):e93, 201