Defining paediatric abusive head trauma using routinely collected patient datasets: Scoping review and testing in a UK cohort

This is the authors' abstract. We don't add key points for this paper.

BACKGROUND: Suboptimal coding and underreporting of abusive head trauma (AHT) makes cases difficult to identify from routinely collected patient data, particularly if not admitted to hospital. OBJECTIVE: To identify existing AHT definitions for routine patient data and compare their impact on AHT incidence estimates when applied to a UK primary care cohort. PARTICIPANTS AND SETTING: Cohort participants were all infants in a large primary care database, who were under 1 year old between January 2013 and June 2021, registered at a General Practice, with linkages to secondary care and Accident and Emergency data. METHOD: A scoping review to identify studies that used diagnostic codes or routinely collected data to define AHT in children under 5 years from electronic health records. We used the definitions identified to calculate incidence per 100,000 person-years in a UK primary care cohort to explore variability of incidence estimates. RESULTS: We identified 40 eligible studies (29 definitions), with most definitions based on hospital data using ICD-9-CM and ICD-10 codes. None applied to a UK population or primary care data sources. Incidence of AHT in our cohort ranged from 9 to 15 per 100,000 person-years using "probable" or "presumptive" definitions, and up to 49 per 100,000 person-years using broader definitions including "possible" AHT. CONCLUSION: The wide range of hospital AHT incidence calculated in our cohort using the definitions identified in the scoping review indicates a need for a standardised definition suited to UK datasets including primary care.