Brief measure of posttraumatic stress reactions: impact of Event Scale-6

Soc Psychiatry Psychiatr Epidemiol. 2010 Mar;45(3):405-12. doi: 10.1007/s00127-009-0073-x. Epub 2009 May 29.


Background: The Impact of Event Scale-revised (IES-R) is one of the most widely used measures of posttraumatic stress reactions. However, for some purposes, such as large epidemiological studies, there is a need for briefer instruments. The aim of this study was to develop and validate an abbreviated version of the IES-R that could capture the three current symptom clusters of posttraumatic stress disorder (PTSD).

Methods: Stepwise multiple regression was applied to abbreviate the IES-R in one sample. The abbreviated version was then tested in three separate samples of individuals exposed to different kinds of potentially traumatic events. Agreement with a reference measure of PTSD, the PTSD checklist (PCL), was calculated for the abbreviated and the full-scale versions of IES.

Results: The abbreviation procedure resulted in a subset of six items (the IES-6), which correlated highly (pooled correlation = 0.95) with the IES-R across samples. Correlations between the IES-6 and IES-R subscales were somewhat lower (r = 0.78-0.94). Both the IES-6 and IES-R were in high agreement with the PCL.

Conclusion: The IES-6 appears to be a robust brief measure of posttraumatic stress reactions. It may be useful for research in epidemiological studies, and it may also have a role as a screening instrument in clinical practice.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Age Distribution
  • Aged
  • Aged, 80 and over
  • Checklist
  • Cluster Analysis
  • Disasters / statistics & numerical data
  • Female
  • Humans
  • Life Change Events*
  • Male
  • Middle Aged
  • Occupational Exposure / adverse effects
  • Personality Inventory / statistics & numerical data*
  • Psychometrics
  • Regression Analysis
  • Reproducibility of Results
  • Stress Disorders, Post-Traumatic / diagnosis*
  • Stress Disorders, Post-Traumatic / psychology
  • Surveys and Questionnaires