Fig. 1

Flowchart of the inclusion process. Index hospital stay refers to any admission to a general hospital with ICD-10 code S06.1-S06.9, S09.7-S09.9 during the study period. GH General hospital, msTBI moderate and severe TBI, RTC Regional trauma centre, TBI Traumatic brain injury. ^†Categorised as borderline mild-to-moderate due to the inability to accurately classify these patients’ TBI severity. For instance, intoxicated patients with an initially low GCS score who regained normal consciousness within 12 h, and severely demented patients with an already reduced GCS score preinjury