Variation in CT use for paediatric head injuries across different types of emergency departments in Australia and New Zealand

Objectives: CT of the brain (CTB) for paediatric head injury is used less frequently at tertiary paediatric emergency departments (EDs) in Australia and New Zealand than in North America. In preparation for release of a national head injury guideline and given the high variation in CTB use found in North America, we aimed to assess variation in CTB use for paediatric head injury across hospitals types. Methods: Multicentre retrospective review of presentations to tertiary, urban/suburban and regional/rural EDs in Australia and New Zealand in 2016. Children aged <16 years, with a primary ED diagnosis of head injury were included and data extracted from 100 eligible cases per site. Primary outcome was CTB use adjusted for severity (Glasgow Coma Scale) with 95% CIs; secondary outcomes included hospital length of stay and admission rate. Results: There were 3072 head injury presentations at 31 EDs: 9 tertiary (n=900), 11 urban/suburban (n=1072) and 11 regional/rural EDs (n=1100). The proportion of children with Glasgow Coma Score ≤13 was 1.3% in each type of hospital. Among all presentations, CTB was performed for 8.2% (95% CI 6.4 to 10.0) in tertiary hospitals, 6.6% (95% CI 5.1 to 8.1) in urban/suburban hospitals and 6.1% (95% CI 4.7 to 7.5) in regional/rural. Intragroup variation of CTB use ranged from 0% to 14%. The regional/rural hospitals admitted fewer patients (14.6%, 95% CI 12.6% to 16.9%, p<0.001) than tertiary and urban/suburban hospitals (28.1%, 95% CI 25.2% to 31.2%; 27.3%, 95% CI 24.7% to 30.1%). Conclusions: In Australia and New Zealand, there was no difference in CTB use for paediatric patients with head injuries across tertiary, urban/suburban and regional/rural EDs with similar intragroup variation. This information can inform a binational head injury guideline.