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


CONCLUSIONS
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.
Thoresen
Siri
S
Norwegian Centre for Violence and Traumatic Stress Studies, Kirkeveien 166, 0407, Oslo, Norway. siri.thoresen@nkvts.unirand.no
Tambs
Kristian
K
Hussain
Ajmal
A
Heir
Trond
T
Johansen
Venke A
VA
Bisson
Jonathan I
JI
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D057189:Checklist; D016000:Cluster Analysis; D004190:Disasters / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008016:Life Change Events; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure / Q000009:adverse effects; D010555:Personality Inventory / Q000706:statistics & numerical data*; D011594:Psychometrics; D012044:Regression Analysis; D015203:Reproducibility of Results; D013313:Stress Disorders, Post-Traumatic / Q000175:diagnosis* / Q000523:psychology; D011795:Surveys and Questionnaires