June 13, 2022

Data Registries in Emergency Care

Emergency Departments are always available and treat anyone who walks through the door. One never knows what challenge the next patient will bring. Throughout the COVID pandemic, ED’s have been extraordinary in their ability to undertake new clinical responsibilities and to accommodate large volumes of critically ill patients. What can data registries do to help?

In the late 1980s, there were no ED data sources.  The only resource was an annual ED volume survey done by the American Hospital Association. Most of the data were estimates.

The CDC developed a family of analytics, collated as the National Center for Health Statistics, beginning in 1960.  The National Hospital Ambulatory Medical Care Survey (NHAMCS) was one instrument, and in 1992, the CDC added an ED surveillance survey.

The emergency department elements of the NHAMCS are based on a sampling methodology that takes some time to compile and verify. The survey publication typically occurs about three years after the data collection. As of January 2022, the latest available report is for care provided in American EDs in the calendar year 2019. It is based on a sampling of 19,481 ED patient care reports [out of approximately 150M visits] from 210ED’s nationally [out of at least 5000]. National population census data is then used to estimate the utilization of ED services. The CDC publishes the data tables without an analysis, and the data is reported only in table form.

The NHAMCS ED survey is a source of aggregate information about ED patients.  But ED leaders need both ED performance and patient-focused data. This helps to plan for immediate and future needs in design, staffing, and hospital support. The NHAMCS-ED survey would only support ED leaders needs if it focused on operating data and performance. 

With no source of data available, a group of ED leaders met in 1994 to develop better practices for ED operations. At the time, ED’s were growing in volume and in importance to the American health system. That initial small group of pioneers became the Emergency Department Benchmarking Alliance (EDBA). It is composed of ED leaders (physicians, nursing, and management)dedicated to improving the quality of emergency care. The emphasis is on metrics, patient satisfaction, medical education, and community service.

In the early 1990s, the EDBA was composed of ED leaders in high volume EDs, which at the time meant more than 100 patients per day. The Alliance now has EDs from every state, volume band, acuity mix. The EDBA annually surveys its membership, asking a small number of well-defined performance measures and descriptive elements.  The EDBA Data Survey includes hospital-based ED’s as well as hospital-affiliated freestanding ED’s.  The data registry now includes annual reporting and trending since 2004.

The EDBA 2020 database report contained performance measures for over 900 EDs that managed over 40 million patient visits, plus 181 additional freestanding EDs that served over 2.8 million patients. In contrast, the NHAMCS-ED survey does not include Freestanding ED’s.  The EDBA data includes adult and pediatric ED’s.

EDBA data cohorts are divided into 20,000 volume bands, as we have found that performance metrics differ with every increase of 20,000 annual visits.  This allows ED leaders to compare the performance of their ED to ones with similar volumes and types of service.  Many years of data and analysis have noted that higher volume EDs have higher acuity, higher use of diagnostic testing, and longer patient processing times.  The trends related to these cohorts remain intact for 2020.  Processing times remain highly correlated with ED volume.

Many groups interested in hospital and emergency department performance now preferentially use the EDBA Data Survey to assess their ED operations.  The EDBA released the 2020 data report to the Joint Commission, AHA, CMS, and CDC.

The EDBA has worked with the CDC to incorporate an analysis of the NHAMCS ED data into the annual EDBA report.  The CDC published the NHAMCS summary tables from 2018in June 2021, and the analysis of that 2018 data is available with the 2020 EDBA report. 

Blending the visit data from the NHAMCS survey with the performance data from the EDBA survey yields important information for emergency care providers and leaders.  Here are key trends:

  • Patients arriving in ED’s are increasingly older, sicker, and have an increased chance of being admitted
  • Many more patients present with illness than injury
  • There has been tremendous growth in the number of patients presenting with mental health or chemical abuse issues
  • Community ED’s are seeing a smaller percentage of children below the age of 18
  • More patients are arriving by EMS (now around 20%). Around 40% of EMS patients are admitted
  • The need for precision in defining patient needs has resulted in more use of diagnostic tools in the ED, especially EKGs. The use of CT scanning appears to have plateaued, but other special imaging procedures [MRI, ultrasound] continue to increase
  • A growing percentage of hospital admissions are funneled through the ED. At least 69% of inpatients are processed through the ED
  • There are more patient transfers, now accounting for about 3.4% of all ED patients. The NHAMCS survey has found that about half of patient transfers from EDs are for mental health treatment
  • Despite increased volumes, flow into and through the ED was improving through 2020. Pandemic operations have likely caused a temporary lag in that performance
  • The number of patients that walk away from the ED “before treatment is complete” was decreasing until 2020. Post-pandemic, there will likely be further improvements in this performance

It is critical that ED leaders understand the data and trends in emergency care. More importantly, they need comparable national data as comparisons to improve local practice.

ACEP will develop the Emergency Medicine Data Institute with many opportunities to collect precise information regarding ED patient care and performance measures. These will enhance the results of the NHAMCS and EDBA surveys. Stay tuned for practice-changing information that will provide better insights for emergency physicians and the patients we serve.

Better data means better patient care.