The International Trauma Questionnaire (ITQ) is an 18 question self-report measure focusing on the core features of Post Traumatic Stress Disorder (PTSD) and Complex PTSD (CPTSD). It was developed to be consistent with the organizing principles of the ICD-11.
The ITQ is designed for diagnosis and can discriminate PTSD from CPTSD by employing validated diagnostic rules. The scale has two major subscales with three symptom clusters in each:
Post Traumatic Stress Disorder (PTSD)
Disturbances in self-organization (DSO)
Disturbances in self-organization are important in the assessment and diagnosis of CPTSD.
The ITQ is useful in the assessment of adults who have experienced trauma and asks them to answer the questions in relation to a specific traumatic event.
During the ITQ’s development, Hyland et al. (2017) evaluated the measure against the 11th version of the International Classification of Diseases (ICD-11) which proposed two related trauma diagnoses: Posttraumatic stress disorder (PTSD) and Complex PTSD (CPTSD). The study assessed the factorial validity of ICD-11 PTSD and CPTSD and provided the first test of the discriminant validity of these constructs is the ITQ.
Cloitre et al. (2018) established the optimal symptom indicators of PTSD and CPTSD by applying item response theory (IRT) analysis to data from a trauma‐exposed community sample (n = 1051) and a trauma‐exposed clinical sample (n = 247) from the United Kingdom.
There are two components of scoring and interpretation: Categorical scoring for the diagnosis of PTSD and CPTSD, and a dimensional component which measures symptom severity.
For PTSD and CPTSD items, endorsement of a symptom or functional impairment item is defined as a score of 2 or greater.
The diagnosis of PTSD is indicated based on the following criteria:
PTSD is indicated if the criteria for PTSD are met and CPTSD is NOT met.
The diagnosis of Complex PTSD (CPTSD) is indicated based on the following criteria:
CPTSD is diagnosed if the criteria for PTSD are met AND criteria for CPTSD are met.
Dimensional scores from 0 to 24 are presented for the two major subscale.
In addition, the four factors under each major subscale are presented (raw score from 0 to 8). Note that the functional impairment factors do not count towards the totals of the major subscales.
Each score is presented as a raw score and a scaled score. The scaled scores are between 0 and 10 and are calculated by dividing the raw score by the maximum possible score, times 10. The scaled scores are useful for comparison between symptom clusters as they are all scored out of 10.
The dimensional scores can be useful in tracking symptoms at the start, middle and end of treatment to ascertain the level of treatment response.
Cloitre, M., Shevlin M., Brewin, C.R., Bisson, J.I., Roberts, N.P., Maercker, A., Karatzias, T., Hyland, P. (2018). The International Trauma Questionnaire: Development of a self-report measure of ICD-11 PTSD and Complex PTSD. Acta Psychiatrica Scandinavica. DOI: 10.1111/acps.12956
Hyland, Shevlin, Brewin, Cloitre, Downes, Jumbe, Karatzias, Bisson, & Roberts. (2017). Validation of post-traumatic stress disorder (PTSD) and complex PTSD using the International Trauma Questionnaire. Acta Psychiatrica Scandinavica, 136(3), 313–322. https://doi.org/10.1111/acps.12771