Acute Stress Disorder Scale (ASDS)

Summary

The ASDS is a 19-item self report measure of acute stress disorder. Questions are based on the DSM-IV criterion and are scored on a 5-point Likert scale

Author/publisher details

© Richard Bryant 1999
Richard A. Bryant, PhD
Professor
School of Psychology
University of New South Wales
Sydney   NSW  2052 
AUSTRALIA

Date

2000 published psychometrics, 1999 copyrighted.

Description

The Acute Stress Disorder Scale (ASDS) is a self-report inventory designed to assess the presence and severity of acute stress disorder (ASD) symptoms. It is based on the DSM-IV criteria and takes approximately 5 minutes to complete. The 19 questions ask respondents to indicate the extent to which they have experienced each symptom on a 5 point scale from " not at all" to "very much". It is the only empirically validated self-report scale for assessing ASD and shows promise as a screening instrument to identify acutely traumatized individuals. The ASDS should be supplemented by clinician interviews for formal diagnosis and for more accurate identification of at-risk individuals.

Scoring and Psychometrics

Scoring
The ASDS is scored by summing the scores (1-5) for all items. Bryant, Moulds & Guthrie (2000) suggest a cutoff score was 56, which identified 91% of those who developed PTSD and 93% of those who did not. The main flaw with this cutoff was that it falsely identified 33% of people as being at risk of developing PTSD but who did not develop PTSD. The optimal formula for scoring the ASDS relative to the ASD diagnosis was to consider the dissociative and other clusters separately. That is, using a cutoff for the dissociative cluster of >-9 combined with a cutoff of >-28 for the cumulative scores on the reexperiencing, avoidance, and arousal clusters. This provided sensitivity of .95, and specificity of .83.

Psychometrics
The ASDS possessed good sensitivity (95%) and specificity (83%) for identifying ASD against the ASD Interview on 99 civilian trauma survivors. Test-retest reliability of the ASDS scores between 2 and 7 days was strong (r = .94). In terms of predictive validity, the ASDS predicted 91% of bushfire survivors who went on to develop PTSD and 93% of those who did not. One third of those identified by the ASDS as being at risk did not develop PTSD, although this is probably more an issue with the diagnosis than the scale itself. A cutoff score of 56 is suggested for identifying individuals who are likely to subsequently develop PTSD: scoring sub-categories of symptoms separately did not increase predictive ability.

Key/core References

Bryant, R. A. (2004). Acute stress disorder - Course, epidemiology, assessment, and treatment. In B. T. Litz (Ed.), Early Intervention for Trauma and Traumatic Loss (pp. 15-33). New York: Guilford Press.

Bryant, R. A., Moulds, M. L., & Guthrie, R. M. (2000). Acute stress disorder scale: A self-report measure of acute stress disorder. Psychological Assessment, 12, 61-68.

Further Information

(e.g., Links)

Copyright Richard Bryant 1999

View manual

There is no manual to accompany this test, but the self-report form is fully self-explanatory. Scoring and interpretation advice is available in the Bryant et.al. (2000) paper or by contacting the authour.

View tool

This resource should be used in an ethical and responsible manner and should be used only for the purpose(s) for which it has demonstrable validity. Please observe copyright where indicated and reference it appropriately.

ISTSS Members: Download ASDS scale