Computed tomography brain scan utilization in patients with headache presenting to emergency departments: a multinational study

Abstract

Background and importance Recommended indications for emergency computed tomography (CT) brain scans are not only complex and evolving, but it is also unknown whether they are being followed in emergency departments (EDs). Objective To determine the CT utilization and diagnostic yield in the ED in patients with headaches across broad geographical regions. Design Secondary analysis of data from a multinational cross-sectional study of ED headache presentations over one month in 2019. Setting and participants Hospitals from 10 participating countries were divided into five geographical regions [Australia and New Zealand (ANZ); Colombia; Europe: Belgium, France, UK, and Romania; Hong Kong and Singapore (HKS); and Turkey). Adult patients with nontraumatic headache as the primary presenting complaint were included. Patients were identified from ED management systems. Outcome measures and analysis The outcome measures were CT utilization and diagnostic yield. CT utilization was calculated using a multilevel binary logistic regression model to account for clustering of patients within hospitals and regions. Imaging data (CT requests and reports) were sourced from radiology management systems. Main results The study included 5281 participants. Median (interquartile range) age was 40 (29–55) years, 66% were women. Overall mean CT utilization was 38.5% [95% confidence interval (CI), 30.4–47.4%]. Regional utilization was highest in Europe (46.0%) and lowest in Turkey (28.9%), with HKS (38.0%), ANZ (40.0%), and Colombia (40.8%) in between. Its distribution across hospitals was approximately symmetrical. There was greater variation in CT utilization between hospitals within a region than between regions (hospital variance 0.422, region variance 0.100). Overall mean CT diagnostic yield was 9.9% (95% CI, 8.7–11.3%). Its distribution across hospitals was positively skewed. Regional yield was lower in Europe (5.4%) than in other regions: Colombia (9.1%), HKS (9.7%), Turkey (10.6%), and ANZ (11.2%). There was a weak negative correlation between utilization and diagnostic yield (r = −0.248). Conclusion In this international study, there was a high variation (28.9–46.6%) in CT utilization and diagnostic yield (5.4–11.2%) across broad geographic regions. Europe had the highest utilization and the lowest yield. The study findings provide a foundation to address variation in neuroimaging in ED headache presentations.