The occurrence of traumatic brain injury (TBI) is a primary cause of mortality and disability worldwide, with moderate-to-severe TBI (mTsTBI) making a significant contribution to this statistic in the United States. However, there is a scarcity of studies that provide prospective, longitudinal outcome data for the acute to chronic phases of recovery after mTsTBI.Objective: The main objective of this study is to evaluate the outcomes in key areas of life function at 2 weeks, 3 months, 6 months, and 12 months post-m Ts TBI. Materials & methods: The ESIC Medical College & Hospital, Faridabad study was conducted the study. The study aimed to prospectively assess longitudinal outcomes with a follow-up period of 12 months post-injury. The study included patients with mTsTBI (Glasgow Coma Scale scores (GCS) of 3-12) who were extracted from a larger group of patients with mild, moderate, or severe TBI. Exposures: Moderate or severe TBI, the GCS and Disability Rating Scale (DRS) were used to assess global functional status at 2 weeks and 3-, 6-, and 12-months post-injury. The GCS scores were dichotomized to determine favorable (scores 13-15) versus unfavorable (scores 3-8) outcomes. Neurocognitive testing and patient-reported outcomes at 12 months post-injury were analyzed.Results: This study involved 100 patients, chosen from a pool of 279 individuals. The participants, including those with severe TBI (n=74) and moderate TBI (n=26), were comparable in terms of demographics and premorbid conditions. At 2 weeks post-injury, 13 out of 74 severe TBI patients and 11 out of 26 moderate TBI patients showed favorable outcomes, as indicated by GCS scores of 13-15. At 12 months post-injury, 40 out of 76 severe TBI patients and 19 out of 26 moderate TBI patients had favorable outcomes, with 14 severe TBI patients and 8 moderate TBI patients reporting no disability. Conclusion: Patients with mTsTBI frequently demonstrated major functional gains, including recovery of independence, between 2 weeks and 12 months post-injury. Severe short-term impairment did not lead to poor outcomes in a substantial minority of patients with mTsTBI. When discussing prognosis during the first two weeks after injury, clinicians should be particularly cautious about making early, definitive prognostic statements suggesting poor outcomes and withdrawal of life-sustaining treatment in patients with m T s TBI