Confirmatory factor analysis of the PTSD Checklist and the Clinician-Administered PTSD Scale in disaster workers exposed to the World Trade Center Ground Zero

Although posttraumatic stress disorder (PTSD) factor analytic research has yielded little support for the DSM-IV 3-factor model of reexperiencing, avoidance, and hyperarousal symptoms, no clear consensus regarding alternative models has emerged. One possible explanation is differential instrumentation across studies. In the present study, the authors used confirmatory factor analysis to compare a self-report measure, the PTSD Checklist (PCL), and a structured clinical interview, the Clinician-Administered PTSD Scale (CAPS), in 2,960 utility workers exposed to the World Trade Center Ground Zero site. Although two 4-factor models fit adequately for each measure, the latent structure of the PCL was slightly better represented by correlated reexperiencing, avoidance, dysphoria, and hyperarousal factors, whereas that of the CAPS was slightly better represented by correlated reexperiencing, avoidance, emotional numbing, and hyperarousal factors. After accounting for method variance, the model specifying dysphoria as a distinct factor achieved slightly better fit. Patterns of correlations with external variables provided additional support for the dysphoria model. Implications regarding the underlying structure of PTSD are discussed.     

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.     

Posttraumatic Stress Disorder Symptom Structure in Chinese Adolescents Exposed to a Deadly Earthquake

This present study examined the structure of posttraumatic stress disorder (PTSD) symptoms in a large sample of Chinese adolescents exposed to a deadly earthquake. A total of 2,800 middle school students aged 12 to 18 years participated in the study 6 months after the “Wenchuan Earthquake”. Results of confirmatory factor analysis indicated that a five-factor intercorrelated model composed of intrusion, avoidance, numbing, dysphoric arousal, and anxious arousal, fit data significantly better than both the four-factor numbing model King et al. (Psychological Assessment 10:90–96, 1998) and the four-factor dysphoria model Simms et al. (Journal of Abnormal Psychology 111:637–647, 2002). Further examination of the external convergent and discriminant validity revealed that except for the dysphoric arousal factor, the remaining four PTSD factors yielded significantly different correlations with external measures of anxiety vs. depression. The findings add to the limited literature on the factor structure of PTSD in youths and on the five-factor PTSD model. In addition, they provide more detail into the latent psychopathological processes of PTSD, and inform the forthcoming DSM-5.     

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.     

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.     

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.     

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.     

Posttraumatic Stress Symptom Clusters,Trauma History,and Substance Use among College Students

Previous research found associations between experiencing specific posttraumatic stress disorder (PTSD) symptom clusters and use of specific substances among combat veterans, women exposed to domestic violence, and an inpatient sample; however, research has not utilized a college sample when considering this association. This study assessed trauma history, PTSD symptoms, alcohol use, and nonexperimental use of depressants, stimulants, opioids, cannabinoids, hallucinogens, inhalants, and steroids in college students. Results indicate unique associations between the PTSD symptom cluster of reexperiencing and use of depressants, avoidance/numbing with use of depressants and opiates, and hyperarousal with use of opiates. Further, the individual subclusters of behavioral avoidance and emotional numbing were associated with use of depressants and avoidance was associated with hallucinogen use. Implications are discussed.     

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.     

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。     

MMPI-2 as a predictor of change in PTSD symptom clusters: a further analysis of the Forbes et al. (2002) data set

In this study, we reanalyzed the Forbes et al. (2002) data set to examine the Minnesota Multiphasic Personality Inventory (MMPI-2; Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989) as a differential predictor of change across posttraumatic stress disorder symptom clusters following treatment in 141 Vietnam veterans. A series of partial correlation and linear multivariate regression analyses, controlling for initial symptom severity, identified several scales predictive of symptom change. None of the MMPI-2 scales, however, emerged as predictors of change in reexperiencing symptoms. Social alienation and marital distress were the most potent predictors for avoidance symptoms. Anger, alcohol use, and hypomania were the most potent predictors for the hyperarousal symptoms. Of the personality disorders, borderline personality was the strongest predictor of change in the avoidance and hyperarousal clusters. Further replication of the findings of this article and those reported by Forbes et al. (2002) is required.     

Holocaust survivors in a primary care setting: fifty years later

Past studies have not assessed the prevalence of emotional disturbances in Holocaust survivors seeking medical treatment in a family practice environment. The present study examined the prevalence of lifetime (the presence of symptomatology at any time) and current posttraumatic stress disorder (PTSD) symptoms, general anxiety, and depression in Holocaust survivors seeking medical treatment in a primary care setting. 20 of the 27 Holocaust survivors in our sample received a current diagnosis of PTSD and reported significant symptoms of depression and general anxiety. Although 74% of the survivors were currently diagnosed with PTSD, participants in this study had reported an overall decline in reexperiencing, hyperarousal, and overall PTSD symptoms but exhibited increased avoidance and numbing symptoms throughout the lifespan. These preliminary results suggest that removing avoidance as a defense mechanism during the course of psychotherapy may leave these survivors without an adequate way for coping with their trauma, subsequently increasing their vulnerability to psychopathology. Implications for psychological interventions are provided.     

Peritraumatic dissociation and experiential avoidance as prospective predictors of posttraumatic stress symptoms

Peritraumatic dissociation (PD) and experiential avoidance (EA) have been implicated in the etiology of posttraumatic stress symptomatology (PTSS); however, the function of these two factors in the onset and maintenance of PTSS following a potentially traumatic event is unclear. The temporal relationships between EA, PD, and the four clusters of PTSS proposed by the Simms/Watson dysphoria model (Simms, Watson, & Doebbeling, 2002) were examined in a three-wave prospective investigation of 532 undergraduate women participating in an ongoing longitudinal study at the time of a campus shooting. Path analyses indicated that preshooting EA predicted greater PD, intrusions, and dysphoria symptoms approximately one month postshooting. PD was associated with increased symptomatology across all four clusters 1-month postshooting, while 1-month postshooting EA was associated with higher dysphoria and hyperarousal symptoms eight months postshooting. PD had a significant indirect effect on all four PTSS clusters eight months postshooting via 1-month postshooting symptom reports. The results suggest that both EA and PD show unique influences as risk factors for PTSS following a potentially traumatic event.     

Alternative Explanations of Emotional Numbing of Posttraumatic Stress Disorder: An Examination of Hyperarousal and Experiential Avoidance

The mechanisms that underlie the emotional numbing symptoms associated with PTSD are not well understood. Studies of Vietnam combat veterans have demonstrated that hyperarousal symptoms predict emotional numbing symptoms more strongly than do other symptoms of PTSD. This study sought to extend these findings through the self-report of 170 female sexual assault survivors. The study also examined whether the relationship between hyperarousal and emotional numbing symptoms was the result of the relationship of each of these to another variable, the tendency to engage in experiential avoidance. Results were consistent with and extended previous findings. Hyperarousal symptoms were also found to predict emotional numbing symptoms above and beyond experiential avoidance, as well as all other symptoms of PTSD.     

Dimensionality of posttraumatic stress symptoms: a confirmatory factor analysis of DSM-IV symptom clusters and other symptom models

Recent exploratory [Taylor, S., Kuch, K., Koch, W. J., Crockett, D. J., & Passey, G. (1998). The structure of posttraumatic stress symptoms. Journal of Abnormal Psychology, 107, 154-160.] and confirmatory [Buckley, T. C., Blanchard, E. B., & Hickling, E. J. (1998). A confirmatory factor analysis of posttraumatic stress symptoms. Behaviour Research and Therapy, 36, 1091-1099; King, D. W., Leskin, G. A., King, L. A., & Weathers, F. W. (1998). Confirmatory factor analysis of the clinician-administered PTSD scale: evidence for the dimensionality of posttraumatic stress disorder. Psychological Assessment, 10, 90-96.] factor analytic investigations suggest that the three symptom clusters of posttraumatic stress disorder (PTSD) as defined in the Diagnostic and Statistical Manual [4th ed.; DSM-IV; American Psychiatric Association (1994). Diagnostic and statistical manual of mental disorders (4th ed.). Washington, DC: Author.] may not provide the best conceptualization of symptom dimensionality. However, the alternative models have not been in agreement, nor have they been compared against each other or models based on the DSM-IV. The purpose of the present investigation was to test a series of dimensional models suggested by these recent factor analytic investigations and the DSM-IV. Using data collected with the PTSD Checklist--Civilian Version [Weathers, F. W., Litz, B. T., Huska, J. A., & Keane, T. M. (1994). PCL-C for DSM-IV. Boston: National Center for PTSD--Behavioral Science Division.] from 349 referrals to a primary care medical clinic, we used confirmatory factor analysis to evaluate a: (1) hierarchical four-factor model, (2) four-factor intercorrelated model, (3) hierarchical three-factor model, (4) three-factor intercorrelated model, and (5) hierarchical two-factor model. The hierarchical four-factor model (comprising four first-order factors corresponding to reexperiencing, avoidance, numbing, and hyperarousal all subsumed by a higher-order general factor) provided the best overall fit to the data; although, all models met some standards specified for good model fit. More research is needed to establish the dimensional nature of PTSD symptoms and to assess whether identified dimensions differ as a function of the trauma experience. Implications for assessment, diagnosis, and treatment are also discussed.     

Development of a Scale to Assess Posttraumatic Stress Disorder

This study presents a newly developed self-report Posttraumatic Stress Scale (PTSS) based on the DSM-IV (American Psychiatric Association, 1994). The scale assesses the trauma experienced by people via the specific criteria of reexperiencing, numbing and avoidance, hyperarousal, and functioning. The instrument was validated on 52 Vietnam veteran subjects diagnosed with posttraumatic stress disorder (PTSD), 64 subjects who were attending professional counseling for trauma-related incidents, and 176 subjects who had never been diagnosed with PTSD or had professional counseling. The test survey comprised the PTSS, Beck's Anxiety Inventory, Beck's Depression Inventory, Impact of Events Scale, the 12-item General Health Questionnaire, Inventory of Depressive Symptomatology, and Symptoms Checklist–90R. The test-retest reliability of the scale was assessed over a four- to six-week period. The scale had a high test-retest reliability and showed high convergent and concurrent validity. Construct validity as assessed through the comparison between the three groups was high; however, factor analysis revealed only two factors instead of the three factors assumed in the DSM-IV. Overall, the scale may be used by clinicians or clients.     

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.     

高唤醒对创伤后应激障碍形成发展的影响及其神经机制

高唤醒是创伤后应激障碍(PTSD)的主要症状之一, 对创伤后应激障碍的形成与发展起核心作用。急性应激期产生的高唤醒可以预测其后PTSD的回避与麻木、再体验等症状的形成, 在创伤后早期, 降低唤醒程度可以减轻PTSD相关的症状表现。下丘脑-垂体-肾上腺轴异常变化会导致去甲肾上腺素(NE)、促肾上腺皮质激素释放因子(CRF)过度释放, 同时皮质醇(酮)水平下降, 这二者是高唤醒产生与维持的主要原因。另外, 5-羟色胺(5-HT)系统的高度激活也影响了高唤醒的形成。食欲素神经肽与NE、CRF与5-HT系统有密切的神经联系, 可能参与高唤醒的调节, 是近年来研究的一个热点。     

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.