A psychometric assessment of Disturbances in Self-Organization symptom indicators for ICD-11 Complex PTSD using the International Trauma Questionnaire

Abstract

Background: Two ‘sibling disorders’ have been proposed for the 11th version of the International Classification of Diseases (ICD-11): Posttraumatic Stress Disorder (PTSD) and Complex PTSD (CPTSD). To date, no research has attempted to identify the optimal symptom indicators for the ‘Disturbances in Self-Organization’ (DSO) symptom cluster. Objective: The aim of the current study was to assess the psychometric performance of scores of 16 potential DSO symptom indicators from the International Trauma Questionnaire (ITQ). Criteria relating to score variability and their ability to discriminate were employed. Method: Participants (N = 1839) were a nationally representative household sample of non-institutionalized adults currently residing in the US. Item scores from the ITQ were examined in relation to basic criteria associated with interpretability, variability, homogeneity, and association with functional impairment. The performance of the DSO symptoms was also assessed using 1- and 2-parameter item response theory (IRT) models. Results: The distribution of responses for all DSO indicators met the criteria associated with interpretability, variability, homogeneity, and association with functional impairment. The 1-parameter graded response model was considered the best model and indicated that each set of indictors performed very similarly. Conclusions: The ITQ contains 16 DSO symptom indicators and they perform well in measuring their respective symptom cluster. There was no evidence that particular indicators were ‘better’ than others, and it was concluded that the indicators are essentially interchangeable.

The validity of ICD-11 PTSD and Complex PTSD in East Asian cultures: findings with young adults from China, Hong Kong, Japan, and Taiwan

“…The present findings are largely consistently with prior work conducted in Western contexts (Cloitre et al, 2018;Hyland et al, 2017b;Karatzias et al, 2017;Shevlin et al, 2018), supporting the validity of the ICD-11 model CPTSD in an Asian context. Specifically, the CFA results demonstrated that across the four samples, the first-and second-order models of CPTSD symptoms fit the respective sample data well (with the exception of the first-order model in the Taiwanese sample where one factor correlation was outside the acceptable boundary).…”

“…The existing literature, predominately derived from 'Western' samples, indicates that the latent structure of the ITQ can be well represented by two models. One model is a correlated six-factor model distinguishing between the PTSD and DSO symptoms at the first-order level, and the second model is twofactor second-order model where the first order correlations are explained by two second-order factors reflecting PTSD and DSO (see Figure 1) (Hyland et al, 2017b;Karatzias et al, 2017;Shevlin et al, 2018). Recent studies have also demonstrated that, in general, the first-order model seems to have better fit in general population samples (Ben-Ezra et al, 2018;Shevlin et al, 2017), whereas the second-order model fits better in clinical or highly traumatized samples (Cloitre et al, 2018;Vallières et al, 2018).…”

Complex PTSD among treatment-seeking veterans with PTSD

“…It is consistent with the overall ICD-11 classification plan for mental disorders to be presented in a 'flatter' horizontal rather than a vertical structure. Furthermore, increasing empirical evidence supports the proposed ICD-11 model of separate PTSD and CPTSD (Brewin et al, 2017;Cloitre et al, 2013;Elklit et al, 2014;Hyland et al, 2017a;Karatzias et al, 2017;Knefel et al, 2015;Shevlin et al, 2018).…”

ICD‐11 PTSD and complex PTSD amongst Syrian refugees in Lebanon: the factor structure and the clinical utility of the International Trauma Questionnaire

“…First, the small, predominately female, treatment‐seeking nature of the sample limits the generalizability of these findings. Second, and while the clinical utility of the ITQ in its current form was supported, the ITQ will eventually be streamlined, with the number of DSO symptoms decreased from 16 to 6 in the near future . Therefore, current findings will require replication once the final iteration of the scale is published.…”

“…More efficient referral systems are particularly important given the current dearth of human resources for mental health and the fraction of funding attributed to mental health, compared to other global health priorities . With plans for further refinement , the ITQ has the potential to be used for more efficient treatment and referral of refugees experiencing trauma‐related psychological distress within in humanitarian settings, where, given the time they take to administer and the requirement that they be administered by a clinician , diagnostic interviews are considered rather impractical. Future research should explore the possibility of task‐shifting/task‐sharing the administration of the ITQ to lower cadre health workers, including community health volunteers and mental health and psychosocial support (MHPSS) workers, as a useful screening tool within primary care and in humanitarian responses.…”