Comparative Effectiveness Research in the Americas on Penetrating Brain Injury: The COMPAS-PBI Study Protocol.

BACKGROUND AND OBJECTIVES: Penetrating brain injury (PBI) is a highly lethal form of traumatic brain injury, with substantial mortality and marked differences across high-income countries and low- to middle-income countries. The aim of the Comparative Effectiveness Research in the Americas on Penetrating Brain Injury (COMPAS-PBI) study was to evaluate management variability, compare outcomes across resource settings, and assess the feasibility of real-time multinational neurocritical care data collection. METHODS: COMPAS-PBI is a multinational, multicenter observational comparative effectiveness study. It includes a retrospective cohort (2021-2025) and a prospective cohort (2026-2028) of adults aged 18 years or older with confirmed PBI, defined by radiographic evidence of dural penetration on head computed tomography, presenting within 24 hours of injury. Eleven trauma centers across 8 countries in the Americas will participate, with the University of Oklahoma Health Sciences Campus serving as the coordinating center. The principal management strategies compared are intracranial pressure monitoring vs no monitoring and neurosurgical intervention, primarily early decompressive craniectomy, vs medical management alone. Comparative analyses will use propensity score-based methods to address baseline confounding. EXPECTED OUTCOMES: The primary outcome is in-hospital mortality. Secondary outcomes include disposition at discharge, Glasgow Outcome Scale-Extended score (at discharge, 6, and 12 months), and timing of intracranial pressure monitoring and decompressive craniectomy. Feasibility outcomes will assess completeness, timeliness, and quality of prospective real-time data capture, particularly in resource-limited settings. DISCUSSION: COMPAS-PBI will generate the first multinational comparative effectiveness data sets focused on civilian PBI within the Americas. The study is expected to provide pragmatic evidence to inform context-sensitive care strategies, reduce practice differences, and support future collaborative neurotrauma research.