Australian Paediatric Acute Code Stroke study: study protocol for a quasi-experimental trial measuring the impact of Code Stroke protocols on time to diagnosis and access to reperfusion therapies.

Introduction: Childhood stroke leads to long-term neurological impairment, impacts on quality of life and has substantial economic costs. Coordinated systems of care are required to streamline rapid diagnosis and treatment of stroke. The primary aim is to investigate the effect of Code Stroke protocols on increasing the proportion of children with stroke diagnosed within the 4.5-hour time window for reperfusion therapies. Methods and analysis: Prospective, multicentre, quasi-experimental interventional study in nine Australian and New Zealand children's hospitals from 2020 to 2026. Children aged 1 month to <18 years with stroke symptoms are eligible for inclusion. A staged pre-implementation and post implementation study design will investigate effects of (1) Code Stroke protocols to streamline diagnosis and treatment, (2) decision support tools to improve diagnostic accuracy and (3) perfusion imaging to quantify brain at risk of infarction. Presenting characteristics, timelines of care, treatments, functional and health economic outcomes will be collected. The primary outcome is the proportion of children with stroke diagnosed within 4.5 hours, estimated using a mixed-effect logistic regression model, with the dichotomous variable time to diagnosis as the dependent variable, implementation phase as the independent fixed effect and hospitals as random effects. Sample size calculation estimates that 98 patients with radiologically confirmed stroke per phase will yield 80% power to detect change from 15% to 40% in the proportion of children diagnosed within 4.5 hours.