BackgroundLarge scale collaborations are required to generate clinical evidence of traumatic brain injury (TBI) treatments. Current evidence is limited and mostly originates from western countries. China has a potential to generate strong evidence, but uncertainty exists how comparable the baseline, treatment and outcome is to other settings. We aimed to document the current care for TBI and its outcome in China by conducting a prospective, multicentre Chinese TBI registry. Methods This prospective, multi-centre, longitudinal, observational study was conducted in 56 centres across China. It collected data of hospitalized patients with a clinical diagnosis of TBI and indication for computerized tomography (CT) scanning. The primary endpoint was survival on discharge. Prognostic analyses were applied to identify predictors of mortality. Variations in mortality were compared between centres and regions within China. Mortality was compared to expected mortality estimated by CRASH basic model. The study was registered with ClinicalTrials.gov, number NCT02210221. Findings From 22nd, Dec, 2014, to 1st, Aug, 2017, 13627 patients with TBI from 56 centers were enrolled in the China CENTER-TBI registry. Data of 13138 patients from 52 hospitals in 22 provinces of China were analyzed. Most patients were male (9782 [74%]), with a median age of 48 (IQR: 33-61). The median Glasgow Coma Scale (GCS) was 13 (IQR: 9-15) and major cause (6548 [50%]) of injury was traffic incident. Overall hospital mortality was 4.8% (637), and in severe TBI 19.7% (552). Age, GCS, Injury Severity Score, pupillary reflex, CT findings, hypoxia and hypotension showed predictive value for mortality. Economic level and altitude of the regions were correlated significantly with death. Variation in mortality existed between centres or regions. The observed mortality was lower than expected (O/E ratio 0•49, 95% CI 0•45-0•53). Interpretation The results show differences in mortality between centres and regions, which indicates potential for identifying best practices in comparative effectiveness research. The risk Powered by Edit orial Manager® and ProduXion Manager® from Aries Syst em s Corporat ion Clinical characteristics and outcomes in patients with traumatic brain injury in China: a prospective, multicentre, longitudinal, observational study