IES-R: Impact of Event Scale-Revised
22-item trauma impact measure with Intrusion, Avoidance, and Hyperarousal subscales. Score 0–88; ≥33 PTSD likely. Most widely used PTSD symptom scale in international trauma research. Weiss & Marmar (1997).
IES-R Score Interpreter
Commonly used clinical convention indicating clinically meaningful symptoms that fall below the full screening threshold. Follow-up assessment warranted.
22 items across Intrusion, Avoidance, and Hyperarousal subscales. Each rated 0–4; sum across all items. Interpreted in reference to a specific traumatic event over the past 7 days.
| Total score | Interpretation |
|---|---|
| 37+ | Severe distressCommonly used clinical convention indicating severe post-traumatic stress response. Warrants urgent clinical assessment. |
| 33–36 | Probable PTSD likely≥33 was identified as the optimal screening cutoff by Creamer, Bell & Failla (2003). Structured clinical evaluation recommended. |
| 24–32 | Moderate/partial PTSD possibleCommonly used clinical convention indicating clinically meaningful symptoms that fall below the full screening threshold. Follow-up assessment warranted. |
| 0–23 | Below screening thresholdScore below the moderate symptoms convention threshold. Ongoing monitoring may still be appropriate following trauma exposure. |
Creamer, Bell & Failla (2003). ≥33 cutoff established in that validation study. The ≥24 and ≥37 thresholds reflect commonly used clinical convention and are not formally established in a single primary source. Educational reference only — not a diagnostic tool.
The IES-R is a 22-item validated measure of subjective distress related to a specific traumatic event. Assesses three PTSD symptom clusters: Intrusion, Avoidance, and Hyperarousal. Score 0–88. Free for clinical and research use. Weiss & Marmar (1997).
What is the IES-R?
The Impact of Event Scale-Revised (IES-R) was developed by Daniel Weiss and Charles Marmar (1997) as an update to the original Impact of Event Scale (Horowitz et al., 1979). The revision added a Hyperarousal subscale to bring the scale into alignment with the DSM-IV PTSD diagnostic criteria. It assesses subjective distress specifically related to a specific traumatic event, making it distinct from general PTSD measures.
The IES-R contains 22 items across three subscales: Intrusion (8 items, intrusive thoughts, images, nightmares), Avoidance (8 items, numbing, avoidance of reminders), and Hyperarousal (6 items, irritability, poor concentration, startle response). Each item is rated on a 5-point scale: 0 (Not at all), 1 (A little bit), 2 (Moderately), 3 (Quite a bit), 4 (Extremely).
The IES-R is free for clinical and research use. It is the most widely used PTSD symptom measure in international trauma research and has been translated into over 20 languages. A total score of ≥33 suggests probable PTSD; ≥37 has been associated with immune function suppression (Weiss, 2007). For DSM-5-TR-aligned PTSD assessment, the PCL-5 is recommended as the primary clinical tool.
Educational reference only. Requires clinical evaluation to confirm PTSD diagnosis.
IES-R Score Interpretation
Weiss & Marmar (1997). Total score cutoffs from Creamer, Bell & Failla (2003) and Weiss (2007).
Trauma Screening Workflows in HiBoop
IES-R alongside PCL-5 and ACE Score, automated scoring and longitudinal tracking for trauma-exposed patients.
Frequently Asked Questions
Is the IES-R self-report or clinician-administered?
The IES-R is a self-report questionnaire completed by the individual. It is not a structured clinician interview. Respondents rate 22 items on a 0–4 scale in reference to a specific traumatic event from the past seven days.
What does a score of 33 or higher mean on the IES-R?
A total IES-R score of ≥33 indicates probable PTSD is likely. Creamer, Bell & Failla (2003) found this threshold (equivalent to a mean item rating of 1.5) provided the best diagnostic accuracy in a sample of Vietnam veterans. It is a screening indicator, not a diagnosis.
Can the IES-R diagnose PTSD?
No. The IES-R is a symptom screener, not a diagnostic tool. A high score supports clinical concern and warrants a structured diagnostic evaluation by a qualified clinician. Only a thorough clinical assessment can establish a PTSD diagnosis.
How is the IES-R scored?
Each of the 22 items is rated 0 (Not at all), 1 (A little bit), 2 (Moderately), 3 (Quite a bit), or 4 (Extremely). Total scores range from 0 to 88. Scores can also be reported by subscale: Intrusion (8 items), Avoidance (8 items), and Hyperarousal (6 items).
References
- 1.Weiss DS, Marmar CR. The Impact of Event Scale-Revised. In: Wilson JP, Keane TM, eds. Assessing Psychological Trauma and PTSD. Guilford Press. 1997:399-411.
- 2.Creamer M, Bell R, Failla S. Psychometric properties of the Impact of Event Scale-Revised. Behav Res Ther. 2003;41(12):1489-96.View source
- 3.Beck JG, Grant DM, Read JP, Clapp JD, Coffey SF, Miller LM, Palyo SA. The impact of event scale-revised: psychometric properties in a sample of motor vehicle accident survivors. J Anxiety Disord. 2008;22(2):187-98.View source
Bill this assessment
The IES-R: Impact of Event Scale-Revised qualifies for reimbursement under these CPT codes (US).
Last reviewed: Jun 3, 2026
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