PTSD’s Underlying Dimensions in Typhoon Haiyan Survivors: Assessing DSM-5 Symptomatology-Based PTSD Models and Their Relation to Posttraumatic Cognition

Abstract

The recent changes in posttraumatic stress disorder (PTSD) symptomatology in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) call for a re-examination of PTSD's latent factor structure. The present study assessed six competing models of PTSD based on DSM-5 symptomatology using confirmatory factor analysis in a sample of young adult Filipino survivors of typhoon Haiyan, one of the strongest typhoons in the world ever recorded at the time of its landfall (N = 632). Furthermore, the differential relationships of the factors of the best-fitting model with posttraumatic cognitions were also investigated. Results showed the 7-factor hybrid model of PTSD comprised of intrusion, avoidance, negative affect, anhedonia, externalizing behaviors, anxious arousal, and dysphoric arousal, to be the best fitting model. In addition, the varying degrees of relationship with posttraumatic cognitions support the distinctiveness of each factor. These findings are pertinent in light of the changes in DSM-5 PTSD symptomatology, as well as in understanding the underlying dimensions of PTSD among Asian, particularly Filipino, survivors of a natural disaster.

Dimensional structure of DSM-5 posttraumatic stress symptoms in Spanish trauma victims

“…However, the statistical comparisons of nested models revealed that the 7-factor Hybrid model did not fit significantly better than the 6-factor Anhedonia model. This result diverges from most of the extant literature assessing the fit of the Hybrid model (Armour, Contractor et al, 2016; Armour et al, 2015; Bovin et al, 2015; Mordeno et al, 2016; Seligowski & Orcutt, 2015; Zelazny & Simms, 2015), but it is consistent with Carragher et al's (2016) and Wang et al's (2015) studies, which also reported similar values of fit indices across the models and found no significant differences in model comparisons between the Anhedonia and Hybrid models. As Carragher et al (2016) suggested, this divergence with previous studies may be related to sample characteristics.…”

“…In this regard, in addition to the aforementioned considerations, the fact that some researchers suggest a possible effect of population type, trauma type, and PTSD measures on the model fit must be highlighted (Elhai & Palmieri, 2011). Furthermore, the high rate of probable PTSD diagnosis in our sample (67.3%) when compared to the rates in previous studies that assessed this model (ranging from 4.02 to 45.9%; Armour, Contractor et al, 2016; Armour et al, 2015; Carragher et al, 2016; Mordeno et al, 2016; Seligowski & Orcutt, 2015; Wang et al, 2015; Zelazny & Simms, 2015) might have contributed, to some extent, to the contradiction of our hypothesis. In fact, Biehn, Elhai, Fine, Seligman, and Richardson (2012) examined differences in PTSD's dimensional structure between Canadian veterans with and without a PTSD diagnosis and found that the models demonstrated a better fit in the sample who did not have a PTSD diagnosis.…”

“…In addition, the type of trauma experience could be another potential explanation for the disparity. In most of the previous studies where the Hybrid model emerged as the best-fitting model, the most endorsed traumatic events were a family member's or close friend's death (Armour, Contractor et al, 2016; Armour et al, 2015) and natural disasters (Mordeno et al, 2016; Wang et al, 2015), whereas in our study the most frequently reported traumatic event was physical violence. Unfortunately, Carragher et al (2016) did not report information on the type of trauma experienced.…”

“…In summary, the 6-factor Anhedonia model and the 7-factor Hybrid model provided a superior fit to the data compared with the 4-factor and 5-factor models— a finding that is reported consistently across studies (Armour, Contractor et al, 2016; Armour et al, 2015; Bovin et al, 2015; Carragher et al, 2016; Mordeno et al, 2016; Seligowski & Orcutt, 2015; Wang et al, 2015; Zelazny & Simms, 2015). However, the findings have not supported the suggestion of a separate externalizing behaviour factor referring to self-initiating aggressive behaviours that may reflect deficits in emotion regulation and impulse control (Tsai et al, 2014).…”

“…Support for the model has also been found in a nationally representative sample of Australian adults (Carragher et al, 2016), in a sample of Philippine young adult survivors of a typhoon (Mordeno, Carpio, Nalipay, & Saavedra, 2016), and in a sample of Chinese adolescent survivors of an earthquake (Wang et al, 2015). The construct validity of the Hybrid model has also been examined with studies finding differential associations between the factors of the model and a broad range of external constructs (e.g., psychiatric comorbidities, posttraumatic cognitions, anger, functioning, or quality of life; Armour, Contractor et al, 2016; Carragher et al, 2016; Mordeno et al, 2016; Pietrzak et al, 2015; Seligowski & Orcutt, 2015; Wang et al, 2015; Zelazny & Simms, 2015). However, in the nationally representative sample of Australian adults, Carragher et al (2016) did not find significant differences in model fit between Anhedonia and Hybrid models.…”