Impact of Event Scale-Revised (IES-R)
Psychology: Mental HealthReliability: Total alpha 0.963 sample items
About this scale
A 22-item measure of subjective distress after a specific traumatic event across three subscales: intrusion, avoidance, and hyperarousal.
Sample item(s)
“Any reminder brought back feelings about it (intrusion)”
“I tried to remove it from my memory (avoidance)”
“I had trouble falling asleep (hyperarousal)”
Reliability
Reported internal consistency: Total alpha 0.96. As a rule of thumb, Cronbach’s α ≥ .70 is considered acceptable, ≥ .80 good, and ≥ .90 excellent for established measures.
Notes
Distinct from the PCL — IES-R focuses on event-specific reactions.
Source & citation
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.
Source. Scale details are summarised from the publication cited above. Always consult the original source for the full item set, scoring, and permission to use.
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