Replication and Longitudinal Measurement Invariance of the PTCI-9

• Published in: Psychological assessment 2022-12, Vol.34 (12), p.1166-1171
• Main Authors: Byllesby, Brianna M., Ripley, Adam J., Palmieri, Patrick A.
• Format: Article
• Language: English
• Subjects: Cognition; Cognitions; Confirmatory Factor Analysis; Factor Analysis, Statistical; Female; Human; Humans; Male; Measurement; Measurement Invariance; Outpatient; Outpatients; Post traumatic stress disorder; Posttraumatic Stress Disorder; Psychometrics; Quantitative psychology; Reproducibility of Results; Stress Disorders, Post-Traumatic - diagnosis; Test Construction; Test Reliability; Test Validity; Test-Retest Reliability; Trauma
• ISSN: 1040-3590; 1939-134X
• DOI: 10.1037/pas0001164

Inflexible negative trauma-related cognitions are a common consequence of trauma exposure and an important indicator of posttraumatic stress disorder. One common measure of trauma-related cognitions is the 36-item Posttraumatic Cognitions Inventory (PTCI; Foa et al., 1999). Recently, a nine-item abbreviated version was developed (PTCI-9; Wells et al., 2019), which may be a reliable alternative with improved model fit. The present study examined the latent factor structure of the PTCI and PTCI-9 in a sample of 185 treatment-seeking outpatients with traumatic stress symptoms to replicate and extend initial findings on the psychometric properties of the PTCI-9. Using confirmatory factor analysis, the correlated three-factor model of the PTCI-9 demonstrated excellent model fit at Time 1 and Time 2 (6 weeks later), as well as strong internal and test-retest reliability. It also exhibited configural, metric, and scalar invariance across time. The present study replicated previous findings that the PTCI-9 may be a psychometrically sound alternative for measuring trauma-related cognitions. Public Significance Statement This study examined the properties of the PTCI-9, a short-form version of the Posttraumatic Cognitions Inventory (PTCI), and found it had good reliability and structural validity. The PTCI-9 may be a psychometrically sound and less burdensome alternative assessment for measuring posttraumatic cognitions in clinical and research contexts.