Description of the Questionnaire

The Impact of Event Scale – Revised (IES-R) is a self-report psychometric tool designed to assess subjective psychological distress related to a specific traumatic event. The questionnaire consists of 22 items referring to the individual’s experiences over the past week. These items are grouped into three distinct subscales: intrusion, avoidance, and hyperarousal. Responses are given on a five-point Likert scale ranging from 0 (not at all) to 4 (extremely), indicating the extent to which each symptom was experienced. The scale has been widely used in both research and clinical settings, with documented reliability and validity.

Purpose

The aim of the IES-R is to measure the psychological impact of a traumatic event by capturing the levels of distress experienced by the individual. It is used for the identification of potential symptoms of post-traumatic stress disorder (PTSD), for initial psychological assessment, for monitoring mental health over time, and for scientific study of trauma outcomes. It can be administered to the general population, clinical patients, and specific groups exposed to crises or disasters.

Scoring

Each of the 22 questions is scored on a scale from 0 to 4, where 0 means “not at all” and 4 means “extremely.” The total score is calculated by summing all item responses, with a possible range of 0 to 88. Interpretation of the total score is indicative and follows these general guidelines: scores below 24 suggest mild psychological impact, scores from 24 to 32 indicate moderate impact, and scores of 33 or above are considered indicative of severe impact, with the potential presence of PTSD. While the tool is not diagnostic, it provides valuable insight into the need for further psychological evaluation.

Data Analysis and Use

Data analysis from the IES-R includes both the calculation of the total score and the individual scores for the three subscales: intrusion, avoidance, and hyperarousal. Results can be analyzed descriptively (e.g., means, standard deviations) or comparatively across groups or over time. The tool is appropriate for use in quantitative research, psychometric assessments, and symptom monitoring. When used in cross-cultural contexts, proper translation and cultural adaptation are required, following standard validation procedures.

References

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). Guilford Press. Horowitz, M., Wilner, N., & Alvarez, W. (1979). Impact of Event Scale: A measure of subjective stress. Psychosomatic Medicine, 41(3), 209–218. Creamer, M., Bell, R., & Failla, S. (2003). Psychometric properties of the Impact of Event Scale–Revised. Behaviour Research and Therapy, 41(12), 1489–1496.