Frequency, cost, and variation in inpatient diagnostic imaging use in children's hospitals.

backgroundDiagnostic imaging studies are frequently utilized when caring for pediatric patients. The most prevalent and costly imaging studies among hospitalized children are unknown.

objectiveIdentify imaging studies with highest frequency, cost, rates of repetition, and hospital variation among hospitalized children, including patients with intensive care (ICU) stays and complex chronic conditions (CCCs).

methodsWe performed a retrospective cohort study of patients hospitalized from January 1, 2021 to December 31, 2022 across 45 children's hospitals in the Pediatric Health Information System. We identified diagnostic imaging studies for inpatient and observation encounters using billing codes grouped by body system and modality. We measured imaging frequency, costs, and variation across hospitals, overall and for ICU stays and children with CCCs.

resultsWe identified 1,523,343 encounters; 59.1% had imaging, with $2.03 billion in imaging costs. The most frequently obtained and repeated imaging included chest X-ray (CXR), abdominal X-ray, and cardiovascular (CV) ultrasound/echocardiography. The imaging studies with highest cumulative cost were cardiovascular ultrasound, CXR, and neuro/head MRI. ICU encounters were 15.1% of total encounters, but accounted for 44.6% of imaging costs; CCC encounters were 39.6% of the total but accounted for 74.2% of costs. Interhospital variation was low among the most frequent and costly imaging modalities.

conclusionsAmong a cohort of hospitalized children, CXR and CV ultrasounds were among the most prevalent, costly, and frequently repeated imaging studies. Encounters with ICU stays and for patients with CCCs incurred disproportionate imaging costs. Our results serve as a starting point for identifying imaging overuse and developing achievable benchmarks of care.