Fig. 1

Participant Flowchart and CONSORT diagram. Flowchart of participant enrollment, inclusion, and data quality assurance from the first visit (V1; approximately 7 days post-injury) and second visit (V2; approximately 4 months post-injury). Blood draws (BD) were obtained from both patients with pediatric mild traumatic brain injury (pmTBI) as well as healthy controls (HC). The interim period refers to the time between study visits when attrition may have occurred. Asterisks (*) denote the number of samples with available blood biomarker data used in final analyses at each visit. The biomarker sample sizes slightly varied relative to clinical data sample sizes due to issues with blood collection or quality assurance. The caret (^) symbol indicates that blood-based biomarker data from two eligible HC was successfully collected at V2 but not V1.