[Hungarian version of the Impact of Event Scale. Psychometric evaluation].

Background: The Impact of Event Scale (IES, Horowitz, 1979) has been widely used to evaluate subjective stress following traumatic life events. Based on the theoretical reflections of the authors, it consists of two subscales: intrusion and avoidance. Although the empirical data of the past 30 years have supported the original two-factor model to a large extent, alternative models have also been published. Our aim was to evaluate the psychometric properties of the Impact of Event Scale Hungarian version.
Methods: Data from 244 undergraduate students on the Hungarian version of Impact of Event Scale (Annus, Perczel Forintos, Kiss, 2005) were analyzed. Subjects were asked to fill in Beck Depression Inventory shortened version (Beck & Beck, 1972, Kopp & Forizs, 1993) and STAI-T (Spielberger, 1970, Sipos & Sipos, 1978) too.
Results: Internal consistency of the whole IES (Cronbach's a=0,891) as well as of intrusion (Cronbach's a=0,874) and avoidance (Cronbach's a=0,818) was found to be very good. Test-retest reliability of the whole scale (r=0,491, p<0,001) as well as of subscales (for intrusion r=0,543 p<0,001, for avoidance r=0,523 p<0,001) was satisfactory. No association was found between gender and IES scores. Confirmatory and explanatory factor analysis supported the two factor model in our sample. IES had a moderate positive correlation with depression (r=0,273, p<0,001) and anxiety (r=0,381, p<0,001), indicating that it reflects a somewhat related but still independent construct.
Conclusions: The Hungarian version of the Impact of Event Scale has been proved a valid and reliable measure of post-traumatic stress symptoms.