Search strategy for PubMed
| Search # | Search term |
| 1 | Brain trauma*[Title] or head injur*[Title] or brain injur*[Title] or head trauma*[Title] or Traumatic Encephalopath*[Title] or TBI[Title] or neurotrauma*[Title] |
| 2 | Age Factors[MeSH] or Old[Tiab] or Older[Tiab] OR geri* [Tiab] OR elder*[tiab] OR ageing[Tiab] or frail*[Tiab] |
| 3 | Outcome*[Tiab] OR Mortality[Tiab] OR surviv*[Tiab] OR prognos*[Tiab] OR death*[Tiab] OR Factor*[Tiab] |
| 4 | 1 AND 2 AND 3 |
| 5 | English[Language] |
| 6 | 4 AND 5 |
| 7 | Filter: before 1 February 2023 |