All incidence

What is incidence?

The incidence of PTSD refers to how many new cases there are per population in a specified time-period after exposure to a specific event. It is different from prevalence, which represents how many overall cases exist.

What is the evidence for overall incidence of PTSD?

Moderate quality evidence finds the overall incidence rate of PTSD after a flood is around 16%. Incidence rates are highest within six months after exposure to flood and in people who experience severe flood intensity.

The overall incidence rate of PTSD after an earthquake is around 24%. Incidence rates are highest within nine months after exposure to earthquake, in females, in people with lower educational levels, in people who had damage to their houses, in bereaved people, in people who had injury to their bodies, and in people who witnessed death during the earthquake.

There were no reviews identified that report incidence rates after exposure to other traumas.

August 2021

Image: ©Sergey Nivens –

Last updated at: 3:22 am, 6th August 2021
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Green - Topic summary is available.
Orange - Topic summary is being compiled.
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