The CAPS is the gold standard in PTSD assessment. The CAPS is a 30-item structured interview that corresponds to the DSM-IV criteria for PTSD. The CAPS can be used to make a current (past month) or lifetime diagnosis of PTSD or to assesses symptoms over the past week.
In addition to assessing the 17 PTSD symptoms, questions target the impact of symptoms on social and occupational functioning, improvement in symptoms since a previous CAPS administration, overall response validity, overall PTSD severity, and frequency and intensity of five associated symptoms (guilt over acts, survivor guilt, gaps in awareness, depersonalization, and derealization).
For each item, standardized questions and probes are provided. As part of the trauma assessment (Criterion A), the Life Events Checklist (LEC) is used to identify traumatic stressors experienced. CAPS items are asked in reference to up to three traumatic stressors.
The CAPS was designed to be administered by clinicians and clinical researchers who have a working knowledge of PTSD, but can also be administered by appropriately trained paraprofessionals. The full interview takes 45-60 minutes to administer, but it is not necessary to administer all parts (e.g., associated symptoms).
The most frequently used scoring rule is to count a symptom as present if it has a frequency of 1 or more and an intensity of 2 or more. A PTSD diagnosis is made if there is at least 1 "B" symptom, 3 "C" symptoms, and 2 "D" symptoms as well as meeting the other diagnostic criteria. Severity scores can also be calculated by summing the frequency and intensity ratings for each symptom. Alternative scoring options have been devised and are described in Weathers, Ruscio & Keane (1999).
B1: Recurrent and intrusive distressing recollections of the event, including images, thoughts, or perceptions.
Have you ever had unwanted memories of (EVENT)? What were they like? What did you remember?
IF NOT CLEAR: Did they ever occur while you were awake, or only in dreams? [EXCLUDE IF MEMORIES OCCURRED ONLY DURING DREAMS]
How often have you had these memories in the past month (week)?
1 Once or twice
2 Once or twice a week
3 Several times a week
4 Daily or almost every day
How much distress or discomfort did these memories cause you? Were you able to put them out of your mind and think about something else? How hard did you have to try? How much did they interfere with your life?
1 Mild, minimal distress or disruption of activities
2 Moderate, distress clearly present but still manageable, some disruption of activities
3 Severe, considerable distress, difficulty dismissing memories, marked disruption of activities
4 Extreme, incapacitating distress, cannot dismiss memories, unable to continue activities
In the past there were different versions of this measure corresponding to different time periods. The CAPS-1 assessed current and lifetime PTSD. The CAPS-2 assessed one week symptom status. These versions were then renamed CAPS-DX (for diagnosis) and CAPS-SX (for symptom). These two versions were later combined into the CAPS, which can be used to assess either symptoms or diagnoses. A version for children and adolescents (CAPS-CA) is also available.
Blake, D. D., Weathers, F. W., Nagy, L. M., Kaloupek, D. G., Gusman, F. D., Charney, D. S., & Keane, T. M. (1995). The development of a clinician-administered PTSD scale. (PDF) Journal of Traumatic Stress, 8, 75-90.
Gray, M., Litz, B., Hsu, J., & Lombardo, T. (2004). Psychometric properties of the Life Events Checklist. (PDF) Assessment, 11, 330-341.
Weathers, F. W., Keane, T. M., & Davidson, J. R. (2001). Clinician-Administered PTSD Scale: A review of the first ten years of research. (PDF) Depression and Anxiety Vol, 13(3), 132-156.
Weathers, F. W., Ruscio, A. M., & Keane, T. M. (1999). Psychometric properties of nine scoring rules for the Clinician-Administered Posttraumatic Stress Disorder Scale. (PDF) Psychological Assessment, 11(2), 124-133.
Orsillo (2001) (PDF) p. 259.
Orsillo, Susan M. (2001). Measures for acute stress disorder and posttraumatic stress disorder. In M.M. Antony & S.M. Orsillo (Eds.), Practitioner's guide to empirically based measures of anxiety (pp. 255-307). New York: KluwerAcademic/Plenum. PILOTS ID 24368
To learn about training to give a CAPS assessment, see CAPS Training Information.
This measure was created by staff at the VA National Center for PTSD. To obtain this scale complete the online request form.
Measure availability: Information on measures is available to everyone. However, the assessment tools themselves can only be distributed to qualified mental health professionals and researchers. We maintain measures developed by affiliated staff of the National Center for PTSD.
See Assessment Measures Specifically for VA Providers and Staff to download the CAPS.