Emergency department visits in Wisconsin 1998-2002: trends in usage and accuracy of reported data.

INTRODUCTION There is a paucity of data regarding the utilization of emergency departments (EDs) across Wisconsin. It is unknown if national trends in increased utilization are consistent within our state. Several years ago, mandatory reporting of ED visits to the Department of Health and Family Services was instituted and, if accurate, may provide a method for tracking ED usage. METHODS We conducted a survey of existing EDs to study the trend in patient visits for the 5-year time period 1998-2003. Data reported in the surveyed departments were compared to those reported to the state database. RESULTS On average, all EDs reported a consistent yearly increase in patient visits over the time period (an average overall increase of 10%). On average, this increase was larger for smaller hospitals. Growth was consistent over the time period, but the yearly rate steadily slowed down. Data reported to the state consistently underreported the actual census. CONCLUSION All sizes of EDs across Wisconsin continue to show increases in ED utilization. The growth rate is consistent but may be slowing. This has implications for planning for ED resources. Reported data have many discrepancies and need to be independently checked before they can be utilized in any research or planning.