PTSD - Tests and diagnosis

The acceptance of a specific disorder called post traumatic stressRelating to injury or concern. disorder (PTSD) is still fairly recent, and the term was only officially introduced in some countries in 1980.[1]

Because of this, there is still some debate about the boundaries at which PTSD should be diagnosed.[1]

Another potentially complicated factor is that PTSD can have a delayed onset, and is sometimes diagnosed decades after the traumatic event.[1]

The criteria for the diagnosisThe process of determining which condition a patient may have. of PTSD can vary from country to country, and depending on the specific guidelines that are used.[2,3] Learn more about the criteria for the diagnosis of PTSD.

PTSD is unusual in that, for a diagnosisThe process of determining which condition a patient may have. to be made, it is important to identify the precipitating factor; that is, the traumatic event that triggered the symptoms of PTSD. It can be difficult to define what constitutes a traumatic event, as this will vary from person to person and there are a number of other variables involved, for example, the duration of the event.[4] Learn more about what constitutes a traumatic event.

Unfortunately, at this stage there are no available tests that can accurately diagnose PTSD.[5] A number of structured interviews exist, however, that can help with this diagnosisThe process of determining which condition a patient may have.: read more about these structured interviews.

Criteria for the diagnosis of PTSD

The exact criteria for the diagnosisThe process of determining which condition a patient may have. of PTSD may vary according to the specific guidelines used. Broadly speaking, however, they include:[2,3]

  • Experiencing or witnessing an event that involves death, injury, or threat to oneself or another person, that would cause great despair for most people
  • The response to this traumatic event must include feelings of fear, helplessness, or horror
  • Frequent re-experiencing of the event through thought intrusions, flashbacks and nightmares
  • Avoidance of any stimuli that trigger memories of the traumatic event
  • Increased symptoms of arousal, including exaggerated startle responses, difficulty concentrating and a change in sleep patterns
  • Symptoms must persist for more than six weeks after the traumatic event, and interfere with the activities of social and occupational life.

The type of traumatic event

Unlike most psychiatric conditions, the diagnosisThe process of determining which condition a patient may have. of PTSD actually rests with identifying the causative factor: that is, the traumatic event.[4]

However, it can be difficult to define exactly what constitutes a traumatic event. Over time, psychiatrists have considered that the event should be one that:[1]

  • Most would find distressing
  • Is objectively distressing; for example, life-threatening
  • Is subjectively distressing; associated with fear and horror.

It can be difficult to define a traumatic event, because the experience of it will be different depending on whether the person is a child or an adult, and events will vary in other factors as well, such as duration. Furthermore, a range of factors are associated with the risk for developing PTSD, not just the event itself. Read more about the risk factors for developing PTSD.[1]

Assessment instruments

There is no predictive test that can accurately diagnose PTSD.[5] However, there are several structured interviews that can help with the diagnosisThe process of determining which condition a patient may have. of PTSD. Examples of these include:[3]

  • The Structured Clinical Interview for DSM-IV
  • The Clinician Administered PTSD Scale
  • The Anxiety Disorders Interview Schedule for DSM-IV.

These interviews are based on the symptoms of PTSD, and the criteria for diagnosisThe process of determining which condition a patient may have. outlined above.

References: 
  1. Stein DJ, Cloitre M, Nemeroff CB et al. Cape town consensus on posttraumatic stressRelating to injury or concern. disorder. CNS Spectr 2009; 14: 1(Suppl 1): 52-8.
  2. Lamprecht F and Sack M. Posttraumatic stressRelating to injury or concern. disorder revisited. Psychosomatic Medicine 2002; 64: 222-37.
  3. Semple D and Smyth R. Oxford Handbook of Psychiatry 2009; 2nd Edition.
  4. Wittchen HU, Gloster A, Beesdo K et al. Posttraumatic stressRelating to injury or concern. disorder: diagnostic and epidemiological perspectives. CNS Spectr. 2009; 14: 1(Suppl 1): 5-12.
  5. Davidson JRT. Surviving disaster: what comes after the trauma? British Journal of Psychiatry 2002; 181: 366-8.