What do systematic reviews say?

Any early psychological intervention vs inactive control (usual care care, attention control, waitlist)

Any early psychological intervention may leads to lower PTSD diagnosis: 3–6 months compared with waiting list/usual care (low certainty).

• Multiple session early psychological interventions for the prevention of post‐traumatic stress disorder 2019 · Cochrane Headline outcomes only
  RR 0.62 [0.41, 0.93]
  5 studies · 758 participants
  Low