|
Measuring the Emotional
Impact of an Event
By Steve B. Reed, LPC, LMSW, LMFT © 2007 |
 |
What is the Impact of Event Scale?
The
Impact of Event Scale (IES) is a short set of 15 questions that can measure the
amount of distress that you associate with a specific event.
Developed in 1979 by Mardi Horowitz, Nancy Wilner, and
William Alvarez, it continues to find use in research and
with mental health professionals worldwide.
The test
is often useful in measuring the impact that you experience
following a traumatic event. Studies show the IES valuable
in spotting both trauma and less intense forms of stress. It
will show how much an impact event is currently bothering
you. The IES is even capable of detecting the affect of the
most severe impact events, those that can leave you
suffering from Post Traumatic Stress Disorder (PTSD).
In 1997,
Daniel S. Weiss and Charles R. Marmar chose to revise the
scale by adding seven additional questions to measure
another dimension of people's reaction to intense stress
events. Both versions have been found to be valid and
reliable.1, 2
I
frequently utilize this tool to measure distress before
providing treatment with the REMAP process and then again, a
week or two after treatment to help measure how much REMAP
has helped.
Here are
the questions and instructions for the original Impact of
Event Scale.
List
Today's Date_________
List the
Date of the Event_________
Describe
the Event______________________________________________
Below is
a list of comments made by people after stressful life
events. Please mark each item, indicating how frequently
these comments were true for you during the past seven
days. If they did not occur during that time, please
mark the "not at all" column.
Select
only one answer per row.
| |
|
Not at all
|
Rarely |
Sometimes |
Often |
|
| 1. |
I
thought about it when I didn't mean to.
|
0 |
1 |
3 |
5 |
|
| 2. |
I
avoided letting myself get upset when I though
about it or was reminded about it. |
0 |
1 |
3 |
5 |
|
| 3. |
I
tried to remove it from memory. |
0 |
1 |
3 |
5 |
|
| 4. |
I
had trouble falling asleep or staying asleep because
of pictures or thoughts about it that came to my mind.
|
0 |
1 |
3 |
5 |
|
| 5. |
I
had waves of strong feelings about it. |
0 |
1 |
3 |
5 |
|
| 6. |
I had
dreams about it. |
0 |
1 |
3 |
5 |
|
| 7. |
I stayed
away from reminders about it. |
0 |
1 |
3 |
5 |
|
| 8. |
I felt as
if it hadn't happened or was un real. |
0 |
1 |
3 |
5 |
|
| 9. |
I tried
not to talk about it. |
0 |
1 |
3 |
5 |
|
| 10. |
Pictures about it popped into my mind. |
0 |
1 |
3 |
5 |
|
| 11. |
Other
things kept making me think about it. |
0 |
1 |
3 |
5 |
|
| 12. |
I was
aware that I still had a lot of feelings about it, but I didn't deal with them. |
0 |
1 |
3 |
5 |
|
| 13. |
I tried
not to think about it. |
0 |
1 |
3 |
5 |
|
| 14. |
Any reminder brought back feelings about it. |
0 |
1 |
3 |
5 |
|
| 15. |
My
feelings about it were kind of numb. |
0 |
1 |
3 |
5 |
|
| |
|
__0__ |
+ ____ |
+ _________ |
+ ___ |
= ___ |
Scoring:
Total each column and add together for a total stress score.
For
example, every item marked in the "not at all" column is
valued at 0. In the "rarely" column, each item is valued at
a 1. In the "sometimes" column every item marked has a
value of 3 and in the "often" column each item is valued at
5. Add the totals from each of the columns to get the total
stress score.
The next
section will help you to understand the significance of your
score.
What Does My Score on the Impact of Event Scale Mean?
The
Impact of Event Scale1 (Horowitz, 1979) and the
Impact of Event Scale-Revised2 (Weiss, 1997) are
useful in measuring how a stressful event may affect you.
For example on the original 15-item Impact of Event Scale (IES),
the scores can range from 0 to 75. You can interpret the
IES scores in the following way:3
Original Impact
of Event Scale (15 questions):
0 –
8 No Meaningful Impact
9 –
25 Impact Event—you may be affected.
26 – 43
Powerful Impact Event—you are certainly affected.
44 – 75
Severe Impact Event—this is capable of altering your
ability to function.
Scores
above 26 are very important. Here are some examples of what
is associated with scores this high.
Score
(IES) Consequence
|
27
or more |
There is a
75% chance that you have Post Traumatic Stress
Disorder
(PTSD).4 Those who do not have full
PTSD may have partial PTSD or at least some of the
symptoms. |
|
35
and above |
This
represents the best cutoff for a probable diagnosis
of PTSD.5 Consider consulting a
mental health professional who is skilled in
treating such issues. |
Revised
Impact of Event Scale (22 questions):
The
revised version of the Impact of Event Scale (IES-r) has
seven additional questions and a scoring range of 0 to 88.
On this
test, scores that exceed 24 can be quite meaningful. High
scores have the following associations.
Score
(IES-r) Consequence
|
24
or more |
PTSD is a
clinical concern.6 Those with scores
this high who do not have full PTSD will have
partial PTSD or at least some of the symptoms. |
|
33
and above |
This
represents the best cutoff for a probable diagnosis
of PTSD.7 |
|
37
or more |
This is
high enough to suppress your immune system's
functioning (even 10 years after an impact
event).8
On the
original IES, a comparable score would be
approximately 39. |
I work
with both the original and revised versions of the Impact of
Event Scale. I find these tests very helpful in measuring
the affect of routine life stress, everyday traumas and
acute stress
References:
-
Horowitz, M. Wilner, N. & Alvarez, W. (1979). Impact of
Event Scale: A measure of subjective stress.
Psychosomatic Medicine, 41, 209-218.
-
Weiss, D.S., & Marmar, C.R. (1997). The Impact of Event
Scale-Revised. In J.P. Wilson & T.M. Keane (Eds.),
Assessing Psychological Trauma and PTSD (pp.399-411).
New York: Guilford.
-
Hutchins, E. & Devilly, G.J. (2005). Impact of Events
Scale. Victim's Web Site.
http://www.swin.edu.au/victims/resources/assessment/ptsd/ies.html
-
Coffey, S.F. & Berglind, G. (2006). Screening for PTSD
in motor vehicle accident survivors using PSS-SR and
IES. Journal of Traumatic Stress. 19 (1): 119-128.
-
Neal, L.A., Walter, B., Rollins, J., et al. (1994).
Convergent Validity of Measures of Post-Traumatic Stress
Disorder in a Mixed Military and Civilian Population.
Journal of Traumatic Stress. 7 (3): 447-455.
-
Asukai, N. Kato, H. et al. (2002).
Reliability and validity of the Japanese-language
version of the Impact of event scale-revised (IES-R-J).
Journal of Nervous and Mental Disease. 190 (3): 175-182.
- Creamer, M. Bell, R. & Falilla, S. (2002). Psychometric
properties of the Impact of Event Scale-Revised.
Behaviour Research and Therapy. 41: 1489-1496.
-
Kawamura, N. Yoshiharu, K. & Nozomu, A. (2001) Suppression
of Cellular Immunity in Men with a Past History of Post
Traumatic Stress Disorder. American Journal of Psychiatry.
158: 484-486
|
