All prevalence

What is prevalence?

Prevalence represents the overall proportion of individuals in a population who have the disorder of interest. It is different from incidence, which represents only the new cases that have developed over a particular time period. Point prevalence is the proportion of individuals in a population who have the disorder at a given point in time (e.g., at one-month post-trauma), while period prevalence is the proportion of individuals in a population who have the disorder over specific time periods (e.g., one to two months post-trauma). Lifetime prevalence is the proportion of individuals in a population who have ever had the disorder and lifetime morbid risk also includes those who had the disorder but who were deceased at the time of the survey.

What is the evidence for overall prevalence of PTSD?

Moderate quality evidence finds the lifetime prevalence of PTSD in the general population is around 3.9%. In people known to have been exposed to trauma, the rate is 5.6%. Rates are highest in high-income countries and in the Western Pacific region.

The prevalence of delayed-onset PTSD is around 5.6% (diagnosis >6 months post-trauma). People showing a delayed onset were mostly veterans and other professionals with earlier subclinical symptoms.

The point prevalence of PTSD reduces over time from 28.8% at one-month post-trauma to 17% at one-year post-trauma. This trend reverses in people exposed to intentional traumas such as war and assault, rather than people exposed to non-intentional traumas such as accidents and natural disasters, with rates increasing from 11.8% at one-month post-trauma to 23.3% at one-year post-trauma after exposure to intentional traumas.

August 2021

Image: ©Sergey Nivens – stock.adobe.com

Last updated at: 3:23 am, 6th August 2021
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Fact Sheet Technical Commentary

NeuRA Libraries

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