Description

The Impact of Event Scale – Revised (IES-R) is a psychometric tool used to assess psychological reactions following traumatic events. This scale provides information about the severity of symptoms related to post-traumatic stress disorder (PTSD) and helps in understanding how individuals are affected by traumatic experiences.

Objective

The main objectives of the Impact of Event Scale – Revised (IES-R) are:
Assessment of reactions to traumatic events: To provide a detailed evaluation of emotional and cognitive responses after traumatic events.
Evaluation of PTSD symptom severity: To help understand the severity and intensity of post-traumatic stress symptoms.
Support for diagnosis and treatment: To use the results to guide diagnosis and therapeutic intervention for individuals exposed to trauma.

Analysis

The analysis of the IES-R includes:
Structure and Content:
The IES-R consists of 22 items covering three core dimensions of PTSD symptoms as defined in the DSM-IV and DSM-5: Intrusion, Avoidance, and Hyperarousal.
Main Dimensions:
Intrusion: Includes questions about flashbacks, nightmares, and intrusive thoughts related to the trauma.
Avoidance: Assesses behaviors aimed at avoiding trauma reminders and emotional responses.
Hyperarousal: Examines nervousness, difficulty concentrating, heightened vigilance, and sleep disturbances.
Rating Scale:
Respondents answer using a 5-point Likert scale, from 0 (“Not at all”) to 4 (“Extremely”), to describe how much they experienced each symptom over the past 7 days.

Calibration

Calibration of the IES-R includes:
Total Score: A cumulative score ranging from 0 to 88, with higher scores indicating greater severity of PTSD symptoms.
Subscales: Scores are calculated for the three dimensions (intrusion, avoidance, hyperarousal), allowing analysis of specific aspects of trauma response.
Both the total score and subscale scores are used to evaluate the need for further treatment and support.

References

Weiss, D. S., & Marmar, C. R. (1997). The Impact of Event Scale – Revised. In Assessing Psychological Trauma and PTSD (pp. 399–411). Guilford Press.
Creamer, M., Bell, R., & Failla, S. (2003). Psychometric Properties of the Impact of Event Scale – Revised. Behaviour Research and Therapy, 41(12), 1489–1496.
Beck, J. G., Grant, D. M., Clapp, J. D., & Palyo, S. A. (2008). Understanding the Interpersonal Impact of Trauma: Contributions of PTSD and Depression. Journal of Anxiety Disorders, 22(2), 284–300.