Comparing posttraumatic stress disorder's symptom structure between deployed and nondeployed veterans

We tested two empirically validated 4-factor models of posttraumatic stress disorder (PTSD) symptoms using the PTSD Checklist: King, Leskin, King, and Weathers' (1998) model including reexperiencing, avoidance, emotional numbing, and hyperarousal factors, and Simms, Watson, and Doebbeling's (2002) model including reexperiencing, avoidance, dysphoria, and hyperarousal. Our aim was to determine which fit better in two groups of military veterans: peacekeepers previously deployed to a war zone (deployed group) and those trained for peacekeeping operations who were not deployed (nondeployed group). We compared the groups using multigroup confirmatory factor analysis. Adequate model fit was demonstrated among the nondeployed group, with no significant difference between King et al.'s (1998) model (separating avoidance and numbing) and Simms et al.'s (2002) similar model involving a dysphoria factor. A better fitting factor structure consistent with Simms et al.'s (2002) model was found in the deployed group. Comprehensive measurement invariance testing demonstrated significant differences between the deployed and nondeployed groups on all structural parameters, except observed variable intercepts (thus indicating similarities only in PTSD item severity). These findings add to researchers' understanding of PTSD's factor structure, given the revision of PTSD that will appear in the forthcoming 5th edition of the Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 2010)--namely, that the factor structure may be quite different between groups with and without exposure to major traumatic events.     

Confirmatory Factor Analysis of the Posttraumatic Stress Disorder Checklist

Several studies have employed confirmatory factor analysis (CFA) to examine the latent structure of the Posttraumatic Stress Disorder (PTSD) Checklist (PCL; Weathers, Litz, Herman, Huska, & Keane, 1993), a measure that assesses PTSD symptomatology. Findings have failed to support the Diagnostic and Statistical Manual of Mental Disorders (4th ed., text revision [DSM–IV–TR]; American Psychiatric Association, 2000) PTSD model, consisting of reexperiencing, avoidance/numbing, and arousal factors, and no consensus has emerged regarding the best fitting alternative model. Additionally, most studies have utilized homogeneous trauma samples. This study used CFA to examine the PCL factor structure in a sample with exposure to various traumatic events. Superior fit was demonstrated by a model specifying reexperiencing, avoidance, dysphoria, and arousal factors.     

Relationships among Dispositional Attributional Style,Trauma-Specific Attributions,and PTSD Symptoms

The learned helplessness model and its various revisions suggest that causal attributions influence responses to events. This study examined relationships among the 3-factor symptom clusters of posttraumatic stress disorder (PTSD) represented in the 4th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM–IV; American Psychiatric Association, 1994) and the individual dimensions of dispositional attributional style and trauma-specific attributions (i.e., internal–external, stable–unstable, global–specific). Relationships among attributions and clusters of PTSD symptoms represented by the 4-factor dysphoria model were also examined. Trauma-specific attributions were most predictive of PTSD symptoms, with higher associations for avoidance and numbing symptoms compared to arousal symptoms in the three-factor model and higher associations for dysphoria symptoms compared to arousal and avoidance symptoms in the four-factor dysphoria model. Results suggest that cognitive vulnerabilities could underlie the comorbidity between PTSD and depression and might represent a high-impact target for treatment.     

地震后青少年创伤后应激障碍的潜在结构分析

为考察地震后青少年创伤后应激障碍（PTSD）的潜在症状结构,本研究采用儿童创伤后应激障碍症状量表和儿童抑郁量表,对汶川地震一年后的746名中学生进行调查。利用验证性因素分析对竞争模型进行比较,结果发现包括侵入性、回避性、麻木性、精神痛苦性唤起和焦虑性唤起等5个症状的PTSD精神痛苦性唤起模型显著优于DSM-IV的PTSD模型、4维情感麻木模型和4维精神痛苦模型。效度分析的结果发现,PTSD精神痛苦性唤起模型具有良好的外部区分效度。所有结果均表明PTSD精神痛苦性唤起模型在汶川地震后青少年群体中具有良好的适用性,可以作为判定震后青少年PTSD症状的有效标准。     

Confirmatory factor analyses of posttraumatic stress symptoms in deployed and nondeployed veterans of the Gulf War

Confirmatory factor analysis was used to compare 6 models of posttraumatic stress disorder (PTSD) symptoms, ranging from 1 to 4 factors, in a sample of 3,695 deployed Gulf War veterans (N = 1,896) and nondeployed controls (N = 1,799). The 4 correlated factors-intrusions, avoidance, hyperarousal, and dysphoria-provided the best fit. The dysphoria factor combined traditional markers of numbing and hyperarousal. Model superiority was cross-validated in multiple subsamples, including a subset of deployed participants who were exposed to traumatic combat stressors. Moreover, convergent and discriminant validity correlations suggested that intrusions may be relatively specific to PTSD, whereas dysphoria may represent a nonspecific component of many disorders. Results are discussed in the context of hierarchical models of anxiety and depression.     

Symptoms of Post-Traumatic Stress Disorder in Bereaved Children and Adolescents: Factor Structure and Correlates

This study investigated the factor structure and correlates of posttraumatic stress-disorder (PTSD) symptoms among children and adolescents confronted with the death of a loved one. Three hundred thirty-two bereaved children and adolescents (aged 8–18; 56.9 % girls) who all received some form of psychosocial support after their loss, completed self-report measures of PTSD, together with measures tapping demographic and loss-related variables, depression, prolonged grief, and functional impairment. Parent-rated indices of impairment were also collected. We first evaluated the fit of six alternative models of the factor structure of PTSD symptoms, using confirmatory factor analyses. Outcomes showed that the 4-factor numbing model from King et al. (Psychological Assessment 10, 90–96, 1998), with distinct factors of reexperiencing, avoidance, emotional numbing, and hyperarousal fit the data best. Of all participants, 51.5 % met DSM-IV criteria for PTSD. PTSD-status and scores on the PTSD factors varied as a function of age and gender, but were unrelated to other demographic and loss-related variables. PTSD-status and scores on the PTSD factors were significantly associated symptom-levels of depression, prolonged grief, and functional impairment. Findings complement prior evidence that the DSM-IV model of the factor structure of PTSD symptoms may not represent the best conceptualization of these symptoms and highlight the importance of addressing PTSD symptoms in children and adolescents seeking help after bereavement.     

The validity of the PTSD checklist as a measure of symptomatic change in combat-related PTSD

Little research to date has examined the ability of self-report measures to assess changes in symptom severity and diagnostic status as a function of treatment. This study investigated the validity of the posttraumatic stress disorder (PTSD) checklist (PCL) as a measure of symptomatic change following programmatic treatment. A sample of 97 Vietnam veterans with combat-related PTSD was assessed using the clinician-administered PTSD scale (CAPS) and the PCL prior to, and 9 months following, participation in a PTSD treatment program. Using the CAPS as the "gold standard" measure of PTSD symptomatology, the PCL demonstrated high diagnostic accuracy pre- and posttreatment. However, significant variations in accuracy were evident in the ability of the PCL to determine the presence and severity of individual symptoms at each time point. In addition, as symptoms improved from pre- to posttreatment, and approached the threshold criteria, the PCL demonstrated reductions in diagnostic accuracy. As a measure of overall symptomatic change, the PCL underrated improvement in comparison to the CAPS. The results supported the use of an overall cut-off score of 50 on the PCL for a diagnosis, and an item score of 3 for symptom criterion, in this population.     

Longitudinal factor structure of posttraumatic stress symptoms related to intimate partner violence

Confirmatory factor analysis (CFA) studies have suggested that a model of posttraumatic stress disorder (PTSD) that is characterized by 4 factors is preferable to competing models. However, the composition of these 4 factors has varied across studies, with 1 model splitting avoidance and numbing symptoms (e.g., D. W. King, G. A. Leskin, L. A. King, & F. W. Weathers, 1998) and the other including a dysphoria factor that combines numbing and nonspecific hyperarousal symptoms (L. J. Simms, D. Watson, & B. N. Doebbeling, 2002). Using the PTSD Checklist (F. W. Weathers, B. T. Litz, D. S. Herman, J. A. Huska, & T. M. Keane, 1993) and CFA, the authors compared these models with competing models. A model of PTSD with 4 intercorrelated factors of Intrusions, Avoidance, Dysphoria, and Hyperarousal was found superior among 396 medical patients who screened positive for intimate partner violence (IPV) and 405 women seeking services for IPV. Structural invariance testing indicated that this 4-factor model remains stable across service setting and time.     

A meta-analytic investigation of the structure of posttraumatic stress disorder symptoms

Converging lines of evidence have called into question the validity of conceptualizations of posttraumatic stress disorder (PTSD) based on the Diagnostic and Statistical Manual of Mental Disorders (DSM; American Psychiatric Association, 2000) and suggested alternative structural models of PTSD symptomatology. We conducted a meta-analysis of 40 PTSD studies (N = 14,827 participants across studies) that used a DSM-based measure to assess PTSD severity. We aggregated correlation matrices across studies and then applied confirmatory factor analysis to the aggregated matrices to test the fit of competing models of PTSD symptomatology that have gained support in the literature. Results indicated that both prominent 4-factor models of PTSD symptomatology yielded good model fit across subsamples of studies; however, the model comprising Intrusions, Avoidance, Hyperarousal, and Dysphoria factors appeared to fit better across studies. Results also indicated that the best fitting models were not moderated by measure or sample type. Results are discussed in the context of structural models of PTSD and implications for the diagnostic nosology.     

Relations Between PTSD and Distress Dimensions in an Indian Child/Adolescent Sample Following the 2008 Mumbai Terrorist Attacks

Posttraumatic stress disorder’s (PTSD) four-factor dysphoria model has substantial empirical support (reviewed in Elhai & Palmieri, Journal of Anxiety Disorders, 25, 849–854, 2011; Yufik & Simms, Journal of Abnormal Psychology, 119, 764–776, 2010). However, debatable is whether the model’s dysphoria factor adequately captures all of PTSD’s emotional distress (e.g., Marshall et al., Journal of Abnormal Psychology, 119(1), 126–135, 2010), which is relevant to understanding the assessment and psychopathology of PTSD. Thus, the present study assessed the factor-level relationship between PTSD and emotional distress in 818 children/adolescents attending school in the vicinity of the 2008 Mumbai terrorist attacks. The effective sample had a mean age of 12.85 years (SD?=?1.33), with the majority being male (n?=?435, 53.8 %). PTSD and emotional distress were measured by the UCLA PTSD Reaction Index (PTSD-RI) and Brief Symptom Inventory-18 (BSI-18) respectively. Confirmatory factor analyses (CFA) assessed the PTSD and BSI-18 model fit; Wald tests assessed hypothesized PTSD-distress latent-level relations; and invariance testing examined PTSD-distress parameter differences using age, gender and direct exposure as moderators. There were no moderating effects for the PTSD-distress structural parameters. BSI-18’s depression and somatization factors related more to PTSD’s dysphoria than PTSD’s avoidance factor. The results emphasize assessing for specificity and distress variance of PTSD factors on a continuum, rather than assuming dysphoria factor’s complete accountability for PTSD’s inherent distress. Additionally, PTSD’s dysphoria factor related more to BSI-18’s depression than BSI-18’s anxiety/somatization factors; this may explain PTSD’s comorbidity mechanism with depressive disorders.     

Factor Structure of the PTSD Checklist in a Sample of OEF/OIF Veterans Presenting to Primary Care: Specific and Nonspecific Aspects of Dysphoria

Although DSM-IV-TR diagnostic criteria for posttraumatic stress disorder (PTSD) include three primary symptom clusters, recent evidence from confirmatory factor analyses suggest that the latent structure of PTSD is better represented by four factors, which will likely be reflected in the upcoming DSM-5. Given this likely transition from three to four clusters, the present study sought to examine specific and non-specific aspects of dysphoria in the factor structure of PTSD symptoms in a sample of OEF/OIF combat veterans presenting to a Veterans Affairs primary care clinic. PTSD symptoms were assessed using the PCL-M (Weathers et al. 1993). Results from confirmatory factor analyses suggested that a dysphoria factor involving a number of non-specific distress symptoms may be an important part of the PTSD symptom profile. After controlling for variance due to general psychological distress, we further found that factor loadings on the dysphoria factor were attenuated but continued to significantly load onto the factor, suggesting that dysphoria may be a specific part of the PTSD symptom constellation.     

Associations between dimensions of anxiety sensitivity and PTSD symptom clusters in active-duty police officers

Prior studies have shown that anxiety sensitivity (AS) plays an important role in posttraumatic stress disorder (PTSD) symptom severity. The purpose of this study was to evaluate associations between empirically supported PTSD symptom clusters (i.e. reexperiencing, avoidance, numbing, hyperarousal) and AS dimensions (i.e. psychological concerns, social concerns, somatic concerns). Participants were 138 active-duty police officers (70.7% female; mean age = 38.9 years; mean time policing = 173.8 months) who, as a part of a larger study, completed measures of trauma exposure, PTSD symptoms, AS, and depressive symptoms. All participants reported experiencing at least one event that they perceived as traumatic, and 44 (31.9%) screened positive for PTSD. Officers with probable PTSD scored significantly higher on AS total as well as the somatic and psychological concerns dimensional scores than did those without PTSD. As well, a higher percentage of officers with probable PTSD scored positively on the AS-derived Brief Screen for Panic Disorder (Apfeldorf et al., 1994) compared with those without PTSD. A series of regression analyses revealed that depressive symptoms, number of reported traumas, and AS somatic concerns were significant predictors of PTSD total symptom severity as well as severity of reexperiencing. Avoidance was predicted by depressive symptoms and AS somatic concerns. Only depressive symptoms were significantly predictive of numbing and hyperarousal cluster scores. These findings contribute to understanding the nature of association between AS and PTSD symptom clusters. Implications for the treatment of individuals having PTSD with and without panic-related symptomatology are discussed.     

Psychometric analyses of the Clinician-Administered PTSD Scale (CAPS)--Bosnian translation

Methods for assessing psychological distress in culturally diverse populations are not firmly established. This study was designed to examine the psychometric properties of the Bosnian translation of the Clinician-Administered PTSD Scale (CAPS; D. D. Blake, F. W. Weathers, L. M. Nagy, D. Kaloupek, G. Klauminzer, D. Charney, et al., 1995) in a Bosnian refugee sample. The authors interviewed 115 help-seeking Bosnian refugees with the CAPS-Bosnian translation to examine its internal consistency and convergent validity, and to provide an assessment of its factor structure. This study demonstrated optimal fit with a 2-factor model of posttraumatic stress disorder (PTSD); the authors also found high reliability with a coefficient alpha of 0.92 and strong convergent validity with instruments measuring depression, anxiety, and levels of psychosocial functioning. Future directions for the assessment of PTSD in cross-cultural populations are discussed.     

Change in posttraumatic stress disorder symptoms: do clinicians and patients agree?

This study assessed the longitudinal association between clinician and patient ratings of posttraumatic stress disorder (PTSD) symptoms over the course of 2 different randomized clinical trials of veterans with chronic PTSD. One trial, the Department of Veterans Affairs Cooperative Study 420 (CSP 420; N = 360) compared trauma-focused and present-centered group therapies, and the 2nd trial compared cognitive processing theory and a waitlist control condition (N = 60). Linear mixed effects modeling revealed significant associations between clinician ratings (Clinician-Administered PTSD Scale; CAPS; D. D. Blake et al., 1990) and patient ratings (Posttraumatic Stress Disorder Checklist; PCL; F. W. Weathers, B. T. Litz, J. A. Herman, J. A. Huska, & T. M. Keane, 1993) in total and symptom clusters of PTSD. Contrary to hypothesis, the amount of change on the CAPS ranged from .75 to .82 standard deviations for every 1 standard deviation change on the PCL. The CAPS and PCL were more closely associated in the trauma-focused vs. present-centered treatment condition in CSP 420, and especially regarding hyperarousal symptoms. When comparing categorization of clinically significant change on the CAPS and PCL, the authors found no differences in the percentages of agreement between clinicians and patients in improvement and exacerbation. The value of multimodal assessment of PTSD treatment outcomes is discussed.     

A confirmatory factor analysis of the Impact of Event Scale using a sample of World War II and Korean War veterans

This study assessed the factor structure of the Impact of Event Scale (IES), a measure of intrusion and avoidance, using a sample of World War II and Korean War veterans who had experienced combat 40-50 years earlier. A series of 3 confirmatory factor analytic models were specified and estimated using LISREL 8.3. Model 1 specified a 1-factor model. Model 2 specified a correlated 2-factor model. Model 3 specified a 2-factor model with additional cross-factor loadings for Items 2 and 12. Model 3 was found to fit the data. In addition, this model was found to be a better explanation of the data than the other models. Also in addition, the correlations between the Intrusion and Avoidance factors and the 4 subscales of the 28-item General Health Questionnaire were examined to determine the distinctiveness of the two IES factors.     

The role of the glutamatergic system in posttraumatic stress disorder

Antiglutamatergic agents, such as lamotrigine, have been used successfully for the treatment of posttraumatic stress disorder (PTSD). They could be potentially acting through the stabilization of the corticotropin-releasing factor (CRF) systems. Glutamate mediates CRF release in various brain regions involved in the pathophysiology of PTSD, antiglutamatergic agents could stabilize the CRF system and, thereby, improve the symptom complex of PTSD (reexperiencing, hyperarousal, and avoidance). The role of glutamate and CRF in PTSD and other anxiety disorders are still being elucidated. However, it is clear that the glutamatergic systems play a role in the pathophysiology of PTSD.     

Assessing PTSD in the military: Validation of a scale distributed to Danish soldiers after deployment since 1998

Since 1998, soldiers deployed to war zones with the Danish Defense (≈31,000) have been invited to fill out a questionnaire on post‐mission reactions. This provides a unique data source for studying the psychological toll of war. Here, we validate a measure of PTSD‐symptoms from the questionnaire. Soldiers from two cohorts deployed to Afghanistan with the International Security Assistance Force (ISAF) in 2009 (ISAF7, N = 334) and 2013 (ISAF15, N = 278) filled out a standard questionnaire (Psychological Reactions following International Missions, PRIM) concerning a range of post‐deployment reactions including symptoms of PTSD (PRIM‐PTSD). They also filled out a validated measure of PTSD‐symptoms in DSM‐IV, the PTSD‐checklist (PCL). We tested reliability of PRIM‐PTSD by estimating Cronbach's alpha, and tested validity by correlating items, clusters, and overall scale with corresponding items in the PCL. Furthermore, we conducted two confirmatory factor analytic models to test the factor structure of PRIM‐PTSD, and tested measurement invariance of the selected model. Finally, we established a screening and a clinical cutoff score by application of ROC analysis. We found high internal consistency of the PRIM‐PTSD (Cronbach's alpha = 0.88; both cohorts), strong item‐item (0.48–0.83), item‐cluster (0.43–0.72), cluster‐cluster (0.71–0.82) and full‐scale (0.86–0.88) correlations between PRIM‐PTSD and PCL. The factor analyses showed adequate fit of a one‐factor model, which was also found to display strong measurement invariance across cohorts. ROC curve analysis established cutoff scores for screening (sensitivity = 1, specificity = 0.93) and clinical use (sensitivity = 0.71, specificity = 0.98). In conclusion, we find that PRIM‐PTSD is a valid measure for assessing PTSD‐symptoms in Danish soldiers following deployment.     

Psychometric evaluation of trauma and posttraumatic stress disorder assessments in persons with severe mental illness

Interrater reliability, internal consistency, test-retest reliability, and convergent validity were examined for the Trauma History Questionnaire (THQ), the Clinician-Administered Posttraumatic Stress Disorder (PTSD) Scale (CAPS), and the PTSD Checklist (PCL) in 30 clients with severe mental illnesses. Interrater reliability for the THQ and CAPS was high, as was internal consistency of CAPS and PCL subscales. The test-retest reliability of the THQ was moderate to high for different traumas. PTSD diagnoses on the CAPS and PCL showed moderate test-retest reliability. Lower levels of test-retest reliability for PTSD diagnoses were related to psychosis diagnoses and symptoms. However, when more stringent criteria for PTSD were used on the CAPS, it had excellent test-retest reliability across all clients. CAPS and PCL diagnoses of PTSD showed moderate convergent validity. The results support the reliability of trauma and PTSD assessments in clients with severe mental illness.     

Testing factor models of the Psychopathy Checklist: Youth Version and their association with instrumental aggression

Although there is a documented link between psychopathy and instrumental violence in adult offenders, the association between these constructs has not garnered significant attention in adolescent offenders. In this study, we evaluated the relationship between psychopathy and instrumental aggression in a sample of 122 male adolescents incarcerated in a state facility for serious and chronic offenders. We evaluated the primary (2-, 3-, and 4-factor) models of the Psychopathy Checklist: Youth Version (PCL:YV; Forth, Kosson, & Hare, 2003) and assessed their relationship to a separate 5-item measure of instrumental violence. CFA revealed good model fit for the 3- and 4-factor latent variable models of adolescent psychopathy and a single-factor model reflecting a 5-item measure of instrumental violence. Structural equation modeling results indicate that the 4-factor model accounted for 20% of the variance for instrumental violence. In contrast, the 3-factor model of the PCL:YV accounted for 8%, and the 2-factor model accounted for 5% of the variance associated with instrumental violence.     

Applicability of traditional and revised models of psychopathy to the Psychopathy Checklist: screening version

Recently, psychopathy has become virtually synonymous with the Psychopathy Checklist (PCL) measures. However, the "gold standard" 2-factor model that underlines these measures has been questioned for its uncertain empirical support and emphasis on antisocial behavior that is not specific to psychopathic personality deviation. This study (N = 870 civil psychiatric patients) compares the fit of the traditional 2-factor model with that of a revised 3-factor model of psychopathy. The revised model better describes the structure of the Screening Version of the PCL (PCL:SV) than the traditional model. Although the revised model's exclusion of some items that assess antisocial behavior reduces the PCL:SV's power in predicting patient violence, this model arguably assesses psychopathy in a more specific, theoretically coherent fashion that may reduce misapplications of the construct. Implications for future research are discussed.