PTSD Checklist (PCL-5)

The PTSD Checklist is a 20-item self-report questionnaire that measures the severity of symptoms of post-traumatic stress disorder over the preceding month. Each item is scored from 0 to 4, giving a total from 0 to 80. The items correspond to the four symptom clusters: intrusion, avoidance, negative changes in mood and thinking, and arousal and reactivity.

It is a screening and monitoring tool, and a score does not diagnose the disorder. A clinical interview is needed to confirm the diagnosis.

Usage. It is used after trauma exposure, in mental health services, in primary care and in research, and to monitor response to treatment.

Indications. Screening after a traumatic event, monitoring of known post-traumatic stress disorder, and assessment of treatment response.

Preparation and technique. The patient completes the checklist in relation to a specific traumatic event identified by the clinician. A companion checklist records the types of traumatic exposure. Completion takes about 5 to 10 minutes.

Contraindications and precautions. Re-experiencing symptoms can be provoked by completion, and the patient is supported during and after. Acute intoxication and psychosis limit reliability.

Interpretation.

• A total of 31 to 33 or more suggests probable post-traumatic stress disorder in many services.
• A provisional diagnosis uses symptom counts in each cluster, with severity rated as moderate (2) or higher.
• A fall of 10 points or more is considered a clinically meaningful response, and a fall of 5 points is a minimum threshold for change.

Causes of a raised score. Post-traumatic stress disorder, acute stress disorder, depression, anxiety, substance use, and complicated grief.

Critical values and findings needing immediate action.

• Suicidal thoughts or self-harm require a same day risk assessment.
• Dissociation with unsafe behaviour or psychosis requires urgent specialist assessment.

Limitations and artefacts. The checklist is a screen and overlaps with depression and anxiety. The time since the trauma affects the interpretation. Cultural expression of distress varies.

Follow up tests. A structured clinical interview for post-traumatic stress disorder, assessment for depression and substance use, and screening for traumatic brain injury where injury accompanied the trauma.

Special groups. Children and adolescents are assessed using age adapted tools. Military, refugee and emergency workers have a higher prior probability.