The objective of this multi-center study is to refine and validate a saliva RNA assessment for youth concussion, yielding a non-invasive test that predicts duration and character of symptoms, and helps guide clinical decisions. To accomplish this goal, the study will enroll 750 youth with mTBI. Saliva RNA levels and symptoms will be assessed at enrollment, 7 days, and 30 days post-injury. Aim 1 will assess the ability of saliva RNA to predict PPCS 30 days after mTBI (defined by reliable change index, or persistence of ≥2 symptoms on day 30, compared with pre-injury state on the Post-Concussion Symptom Inventory; PCSI). RNA accuracy will be compared to a validated clinical prediction tool (5p tool). Aim 2 will assess the ability of saliva RNA levels to identify recovered participants on day 30. RNA accuracy will be compared to change in composite score on a standardized reaction time test (from enrollment to day 30). Completion of these aims will yield an objective biologic test that can be used for prognosis at the time of mTBI, and to aid clinical decisions regarding return-to-learn or return-to-play.
