Defining frequent emergency department users using ICD-9 codes and targeting these groups with EMS based interventions

Background:

Research on frequent emergency department users does not provide a standard definition for what qualifies an individual as a frequent ED user. Diagnostic group codes may be a viable method of defining individuals by number of visits as “normal”, “frequent”, or “super” users. Interventions can be targeted to the frequent or super user groups.

Methods:

Nevada UB-10 hospital discharge data submitted to the Nevada Division of Healthcare Finance and Policy were used. Patient demographics, unique ID, diagnoses, etc. are included in the UB-10 system. Unique IDs were used to identify those patients who visited the ED 1-2 (normal), 3-11 (frequent), and 12 or more times (super) in a given year. This resulted in 313,998 ED visits being included in the study. SAS 9.3 software, crosstab frequency, and chi-square tests were used to measure association between visit level and various factors.

Results:

Results of the study show hospital diagnostic group codes are different for patients in each ED visit group. Differences in zip code of frequent and super users compared to normal ED users were found. Cost per visit of “normal” users averaged $5,600 while cost of “frequent” users averaged $4,300 and “super users” averaged $4,000.

Conclusion:

Use of diagnostic group codes to describe individuals in different ED visit levels is a viable method to characterize conditions associated with frequent ED use. Cost of care/visit for frequent and super users provide further evidence for lower acuity complaints, and suggest these are patients with chronic health problems that cannot be addressed in an ED.