The Development of Customized Overcrowding Index for an Emergency Department

Ko, Jong Myoung; Son, Ji Hun; Ahn, Yong Deok; Lee, Kee Heon; Yang, Seung Whan; Kim, Seung Ho; Park, Yu Suk; Lee, Young Hoon

Abstract

PURPOSE: Emergency department (ED) overcrowding results in loss in timely, effective medical care, as well as in social and economical efficiency. This paper proposes a new overcrowding index to reduce and to prevent these losses.
METHODS
We investigated the real-time situation of the emergency department in a major Korean hospital, compared to existing indices and to extracted factors to develop a new, customized overcrowding index based on the flow of patients, a reflection of emergency room conditions. We developed 3 indices, FFOI (Front Flow Overcrowding Index), BFOI (Back Flow Overcrowding Index), and TFOI (Total Flow Overcrowding Index). Each index was applied to test the period from 10 September 2007 to 16September 2007. We extracted values of each index at 3- hour intervals and estimated how they reflected the overcrowding situation compared with basic overcrowdingindices. We used the correlation coefficient and Kullback- Leiblur (KL) distance as the basis for measurement.
RESULTS
Existing indices are emergency department work index (EDWIN), national emergency department overcrowding scale (NEDOCS), and real-time emergency analysis of demand indicator (READI) work score (WS). EDWIN and READI did not reflect accurately the overcrowding situation. Some factors extracted from NEDOCS and WS were not suited to the emergency department. We solved these problems by develop in new indices.
CONCLUSION
In conclusion, the new indices are more effective and descriptive than the existing indices with respect to correlation to crowdedness in the emergency department. In the future, the new, customized overcrowding index will become more descriptive if the necessary data is gathered in real time and more effectively verified by the medical staffs and patients.