DTS™

Startle, Physiological Arousal, Anxiety, and Numbness (SPAN)

Based on the DTS assessment, this 4-item questionnaire screens for critical indicators of Posttraumatic Stress Disorder. Respondents are asked to refer to a particular traumatic event or series of events and designate symptom severity within the past week using a 5-point rating scale. The SPAN scale is ideal for use in primary care offices, multidiscipline clinics, and for research purposes. A total score is used to indicate which clients could be referred for more comprehensive screening and follow-up, including a DTS administration.

Respondents are asked to rate each of the 17 items referring to a particular traumatic event, or series of events, according to level of distress based on their ratings of symptoms that have occurred during the past week. Both frequency and severity are rated for each item. If the respondent has experienced multiple traumatic episodes, multiple copies of the DTS may be administered.

A total score, reflecting both frequency and severity ratings for all 17 items and separate ratings for the total frequency and total severity of all 17 items, can be used to interpret results. The 3 clusters—Intrusive, Avoidance/Numbing, and Hyperarousal—can be scored separately as well. Intrusion symptoms are covered in 5 items corresponding to Cluster B in DSM-IV^™; 7 items correspond to Avoidance and Numbing, Cluster C in DSM-IV^™; and 5 items correspond to Hyperarousal, Cluster D in DSM-IV^™. A table that gives relative frequencies for individuals with and without PTSD at given DTS scores is also integrated into the form. This table aids in the interpretation of the respondent’s Total DTS score.

The DTS is suitable for adults who have an eighth-grade reading level or higher and is appropriate for both individual and group administrations.

Scientific Validation

Because the DTS items were selected to represent each of the defining symptoms of Post-Traumatic Stress Disorder in DSM-IV^™, the scale can be useful in assessing diagnostic probability and the frequency and severity of PTSD symptoms.

Detailed data are presented, including:

• split-half reliability, between occasion reliability (i.e., test retest), and internal consistency co-efficients
• diagnostic sensitivity, specificity, predictive value, and efficiency of the DTS relative to an independent SCID diagnosis of PTSD
• convergent validity as supported by a comparison with three other psychometric measures
• divergent validity as supported by the failure of the DTS to show statistically significant associates with measures unrelated conceptually to the severity of PTSD
• evidence for the construct validity of the DTS lies in the ability of the Total DTS Score to distinguish, by means of an independent clinical interview, between respondents diagnosed with PTSD and those without the diagnosis
• additional evidence to show that the DTS is able to distinguish between people who respond to treatment and those who fail to respond
• the ability of the DTS to show change across time and to separately distinguish between varying levels of severity

The DTS was developed and tested in broad-based samples totaling over 400 subjects, inclusive of men and women and different traumata. Subjects were recruited from four clinical research studies of PTSD groups. Study 1 was composed of 78 female rape victims in treatment at Duke University Medical Center, North Carolina. Study 2 included 53 Hurricane Andrew victims from Florida. Study 3 consisted of 110 male combat veterans seen at Durham Veterans' Administration Medical Center, North Carolina. Study 4 consisted of 102 individuals in a multi-center clinical trial throughout the United States The DTS Manual documents specific demographic aspects of the sample.