BACKGROUND: In post-traumatic stress disorder (PTSD) there is a need for 
self-rating scales that are sensitive to treatment effects and have been tested 
in a broad range of trauma survivors. Separate measures of frequency and 
severity may also provide an advantage.
METHODS: Three hundred and fifty-three men and women completed the Davidson 
Trauma Scale (DTS), a 17-item scale measuring each DSM-IV symptom of PTSD on 
5-point frequency and severity scales. These subjects comprised war veterans, 
survivors of rape or hurricane and a mixed trauma group participating in a 
clinical trial. Other scales were included as validity checks as follows: Global 
ratings, SCL-90-R, Eysenck Scale, Impact of Event Scale and Structured Clinical 
Interview for DSM-III-R.
RESULTS: The scale demonstrated good test-retest reliability (r = 0.86), 
internal consistency (r = 0.99). One main factor emerged for severity and a 
smaller one for intrusion. In PTSD diagnosed subjects, and the factor structure 
more closely resembled the traditional grouping of symptoms. Concurrent validity 
was obtained against the SCID, with a diagnostic accuracy of 83% at a DTS score 
of 40. Good convergent and divergent validity was obtained. The DTS showed 
predictive validity against response to treatment, as well as being sensitive to 
treatment effects.
CONCLUSIONS: The DTS showed good reliability and validity, and offers promised 
as a scale which is particularly suited to assessing symptom severity, treatment 
outcome and in screening for the likely diagnosis of PTSD.