Changes in Emergency Department Imaging: Perspectives From National Patient Surveys Over Two Decades

Purpose: To use patient-generated data to assess the changing role of emergency department (ED) imaging for a spectrum of clinical indications.

Methods: The Household Component Emergency Room Visits File was obtained from 1996 through 2014 for the Medical Expenditure Panel Survey, a nationally representative survey of US households. Percentage of visits associated with various imaging modalities was computed annually, stratified by respondents' self-reported primary condition during the visit. Modality characteristics were assessed for conditions most frequently imaged in 1996 or 2014.

Results: For most conditions, use of advanced imaging (defined by Medical Expenditure Panel Survey as CT or MRI) in the ED increased significantly (P < .001). The largest growth occurred for urinary calculus (from 0% to 48.5%) and headache (from 17.5% to 33.3%), which were the most commonly imaged conditions by CT or MRI in 2014. For ultrasound, the most commonly imaged condition was pregnancy in 1996 (32.9%) and 2014 (44.5%). No other condition was associated with ultrasound in >20% of visits. For radiography, the most commonly imaged conditions were extremity wounds and fractures in 1996 (range 84.5%-90.2%) and 2014 (range 93.4%-93.9%). Use of radiography decreased for urinary calculus from 67.4% to 24.2% (P < .001).

Conclusion: For many conditions, ED utilization of advanced imaging increased significantly, though growth was variable across conditions. In certain scenarios, advanced ED imaging is adding to, rather than replacing, other modalities. Ultrasound and radiography utilization was overall unchanged. That national patient survey data mirror traditional claims-based studies suggests an expanded role for patient-generated data in identifying areas of imaging utilization that may benefit from targeted optimization efforts.