The Impact of Event Scale—Revised: evaluation of the subscales and correlations to psychophysiological startle response patterns in survivors of a life-threatening cardiac event: An analysis of 129 patients with an implanted cardioverter defibrillator

Baumert, Jens; Simon, Heidi; Gündel, Harald; Schmitt, Claus; Ladwig, Karl-Heinz

doi:10.1016/j.jad.2003.09.006

« Previous Next »Journal of Affective Disorders
Volume 82, Issue 1 , Pages 29-41, 1 October 2004

The Impact of Event Scale—Revised: evaluation of the subscales and correlations to psychophysiological startle response patterns in survivors of a life-threatening cardiac event:

An analysis of 129 patients with an implanted cardioverter defibrillator

Jens Baumert
- Institut und Poliklinik für Psychosomatische Medizin, Psychotherapie und Med. Psychologie Universitätsklinikum rechts der Isar der Technischen Universität München, Langerstraße 3-81675, Munich, Germany
- National Research Center for Environment and Health (GSF), Institute of Epidemiology, Germany
Heidi Simon
- Institut und Poliklinik für Psychosomatische Medizin, Psychotherapie und Med. Psychologie Universitätsklinikum rechts der Isar der Technischen Universität München, Langerstraße 3-81675, Munich, Germany
Harald Gündel
- Institut und Poliklinik für Psychosomatische Medizin, Psychotherapie und Med. Psychologie Universitätsklinikum rechts der Isar der Technischen Universität München, Langerstraße 3-81675, Munich, Germany
Claus Schmitt
- Deutsches Herzzentrum München, Klinik an der Technischen Universität München, Munich, Germany
Karl-Heinz Ladwig
- Corresponding author. Institut und Poliklinik für Psychosomatische Medizin, Psychotherapie und Med. Psychologie Universitätsklinikum rechts der Isar der Technischen Universität München, Langerstraße 3-81675, Munich, Germany. Tel.: +49-89-4140-4399; fax: +49-89-4140-4845.
- Institut und Poliklinik für Psychosomatische Medizin, Psychotherapie und Med. Psychologie Universitätsklinikum rechts der Isar der Technischen Universität München, Langerstraße 3-81675, Munich, Germany
- National Research Center for Environment and Health (GSF), Institute of Epidemiology, Germany

Received 24 January 2003; received in revised form 17 September 2003; accepted 22 September 2003.

Abstract

Background: The aim of the present study was to examine the reliability and validity of the Impact of Event Scale—Revised (IES-R) with special emphasis on the evaluation of the hyperarousal subscale against a standardized psychophysiological measurement. Methods: A total of 129 survivors of a life-threatening cardiac event underwent a psychodiagnostic evaluation and a psychophysiological acoustic startle reflex (ASR) paradigm. The ASR assessed the magnitude and habituation of electromyogram (EMG) and skin conductance responses (SCR) in response to the delivery of 15 acoustic startle trials. Pearson correlation and factor analysis was used to measure reliability and construct validity. The hyperarousal subscale was validated against the ASR in terms of sensitivity and specificity mainly using receiver operating characteristic (ROC) curve analysis. Results: A high reliability was found for the intrusion and avoidance subscale (α>0.8); however, the hyperarousal subscale showed a weaker reliability (α=0.66). No avoidance item, one intrusion item but four hyperarousal items revealed higher correlations to another than its assigned subscale. The hyperarousal subscale was not able to discriminate sufficiently between patients with and without exaggerated startle reactions as indicated by ROC curves running near the diagonal line. Limitations: The scores in all three subscales are lower compared to subjects traumatized by non-cardiac events. Conclusions: Reliability and construct validity for the intrusion and avoidance subscale proved to be high but was only sufficient for the hyperarousal subscale. Moreover, the criterion validity of the hyperarousal subscale regarding psychophysiological measurements is arguable and indicates further investigations in this area.

Keywords: Posttraumatic stress disorders, Hyperarousal, Startle reactions, Psychophysiological assessment, Sensitivity and specificity