Unmasking Verbal Defensiveness: The Role of Psychological Threat in Sentence Completion Tests.

Shedding light on the validity of sentence completion test (SCT) verbal defensiveness as an index of defensive behavior, the current two-part study examined the relationship between psychological threat and verbal defensiveness among military security and mission-critical team candidates using SCTs. Our study showed that as the threatening nature of SCT stems increased, defensive responses also increased, substantiating the link between psychological threat and defensive behavior. In addition, expert ratings of stem content revealed moderately strong relationships with defensive responses across two different SCTs, irrespective of their structural characteristics. In contrast to previous studies using total verbal defensiveness scores, we examined specific defensive response types and their associations with stem threat ratings, finding that omissions, denial, and comments about the test were linked to stem threat levels. Lastly, our study extends the application of the SCT verbal defensiveness index beyond specialized personnel selection, finding no significant differences in verbal defensiveness based on gender or military status. Overall, these findings contribute to a comprehensive understanding of defensive behavior and its contextual variations.

Changes in mood, fatigue, sleep, cognitive performance and stress hormones among instructors conducting stressful military captivity survival training.

Numerous studies have examined the effects of captivity survival training on psychological and physiological function in trainees. In the present study we shifted the focus to instructors, and measured the effects that the delivery of training exerts on their levels of stress and performance. Because instructors are called upon to perform difficult duties (e.g., mock interrogations) under extreme conditions, we hypothesized that significant increases in psychological and physiological indices of stress would occur due to training. In addition, as part of their job tasking, the instructors conducted courses in consecutive weeks. This offered a unique and ecologically valid opportunity to assess carryover of stress from one week to the next. We hypothesized stress levels would be higher in the second than the first week of training. Our first hypothesis was supported: Delivering training was associated with impairments in mood, fatigue, and sleep, as well as a reduction in the ratio of testosterone/cortisol level in blood. Our second hypothesis was largely not supported as a 3-day break separating consecutive courses appeared sufficient for restoring psychological and physiological function. Our results demonstrate that although the delivery of training exerts negative effects on instructors' levels of stress, the 3-day recovery period separating consecutive courses is sufficient to return psychological and physiological function to baseline levels.

Psychological Perspectives on Interrogation.

Proponents of "enhanced interrogation techniques" in the United States have claimed that such methods are necessary for obtaining information from uncooperative terrorism subjects. In the present article, we offer an informed, academic perspective on such claims. Psychological theory and research shows that harsh interrogation methods are ineffective. First, they are likely to increase resistance by the subject rather than facilitate cooperation. Second, the threatening and adversarial nature of harsh interrogation is often inimical to the goal of facilitating the retrieval of information from memory and therefore reduces the likelihood that a subject will provide reports that are extensive, detailed, and accurate. Third, harsh interrogation methods make lie detection difficult. Analyzing speech content and eliciting verifiable details are the most reliable cues to assessing credibility; however, to elicit such cues subjects must be encouraged to provide extensive narratives, something that does not occur in harsh interrogations. Evidence is accumulating for the effectiveness of rapport-based information-gathering approaches as an alternative to harsh interrogations. Such approaches promote cooperation, enhance recall of relevant and reliable information, and facilitate assessments of credibility. Given the available evidence that torture is ineffective, why might some laypersons, policymakers, and interrogation personnel support the use of torture? We conclude our review by offering a psychological perspective on this important question.

The effects of captivity survival training on mood, dissociation, PTSD symptoms, cognitive performance and stress hormones.

In the Canadian Armed Forces (CAF), Conduct After Capture (CAC) training is a 4-day captivity survival course during which soldiers are exposed to increasing stress, and evaluated on their ability to accomplish military objectives. We hypothesized that: (a) compared to baseline, CAC training would cause significant, reversible perturbations in measures of psychological functioning and serum and salivary stress hormone levels relevant to models of stress hardiness and vulnerability; and (b) deviations from baseline would be maximal at the time point of most intense stress during training. CAF personnel were assessed at baseline, twice during training (immediately prior to a less challenging interrogation role-play scenario and again following another much more intense interrogation role-play scenario), and after completion of training. At each occasion, mood, fatigue, dissociation, PTSD symptoms, short-term and working memory, and salivary cortisol and dehydroepiandrosterone (DHEA) were assessed. As predicted, scores on all measures were degraded during CAC but recovered after completion of training, and almost all measures were most degraded at the more intense interrogation role-play scenario. Unexpectedly, memory performance was unaffected by training, suggesting that a short duration of intense stress might be insufficient for degrading it. Another unexpected finding was that mood assessed prior to training predicted successful completion of training, which bears important practical implications for increasing the success rate of training in similar environments. These results demonstrate that despite its relative brevity, CAC training nevertheless induces significant but reversible effects on psychological and physiological function-necessary preconditions for stress inoculation training.

How Personality Affects Vulnerability among Israelis and Palestinians following the 2009 Gaza Conflict.

Can the onset of PTSD symptoms and depression be predicted by personality factors and thought control strategies? A logical explanation for the different mental health outcomes of individuals exposed to trauma would seem to be personality factors and thought control strategies. Trauma exposure is necessary but not sufficient for the development of PTSD. To this end, we assess the role of personality traits and coping styles in PTSD vulnerability among Israeli and Palestinian students amid conflict. We also determine whether gender and exposure level to trauma impact the likelihood of the onset of PTSD symptoms. Five questionnaires assess previous trauma, PTSD symptoms, demographics, personality factors and thought control strategies, which are analyzed using path analysis. Findings show that the importance of personality factors and thought control strategies in predicting vulnerability increases in the face of political violence: the higher stress, the more important the roles of personality and thought control strategies. Thought control strategies associated with introverted and less emotionally stable personality-types correlate positively with higher levels of PTSD symptoms and depression, particularly among Palestinians. By extension, because mental health is key to reducing violence in the region, PTSD reduction in conflict zones warrants rethinking.

Spontaneous and deliberate dissociative states in military personnel: relationships to objective performance under stress.

We recently distinguished between spontaneous and deliberate dissociative states in military personnel exposed to stressful survival training, demonstrating not only that a substantial subset of participants (13%) deliberately dissociate under intense stress but also that most deliberate dissociators (76%) find it helpful (facilitative) to coping. In this brief report, we examine the relationship between spontaneous and deliberate subtypes of dissociation, and objective military performance in Special Forces and non-Special Forces personnel enrolled in survival school. Inverse relationships between dissociation and military performance were observed in both Special Forces and general soldier subgroups. Military performance did not differ between spontaneous and deliberate dissociators, nor did it differ between those who appraised dissociative states as facilitative versus debilitative to stress coping. This study evolves our understanding of factors influencing human performance in the high-stakes survival context.

Efficacy of combining interview techniques in detecting deception related to bio-threat issues.

The purpose of this project was to assess the detecting deception efficacy of three well-validated "detecting deception" methods - i.e., forced choice testing (FCT), modified cognitive interviewing (MCI) and autobiographical implicit association testing (aIAT) - when applied to the issue of bio-threat. The detecting deception accuracies of FCT and MCI were 81% and 75%, respectively. Although the aIAT mean response times in block 5 differed significantly between deceptive and truthful persons, the classification accuracy was low. FCT alone reduced the group of 64 persons to 11 and detected 50% of the liars; the false positive rate was 9%. MCI alone reduced the group of 64 to 24 and detected 92% of the liars; the false positive rate was 54%. When FCT was paired with MCI, 75% of liars were detected and the false positive rate was 13%. Forced choice testing and MCI show promise as methods for detecting deception related to bio-threat under low-base-rate conditions. These methods took little time, enhanced the odds of detecting deceptive individuals and exhibited high positive likelihood ratios, suggesting that they have merit as screening tools. The aIAT required more time and was less accurate but may still serve as a useful screening tool.

Perspective: I believe what I remember, but it may not be true.

A growing number of research findings have challenged the conception that memory for traumatic events is highly accurate or even indelible in nature. Research involving soldiers indicates that realistic levels of high stress decrease the accuracy of eyewitness memory. In addition, recent findings from several studies show quite clearly that memories for stressful events - including those from combat trauma - are malleable and vulnerable to alteration by exposure to misinformation. Under high stress, our brains facilitate the formation of "gist" memories that allow us to avoid future dangers but which may not contain the detail and precision demanded by the judicial system. Although mental health professionals ought to play a role in educating the courts about mental illness and trauma, it is unwise for them to become advocates for the idea that traumatic memories are indelible, factual accounts of events.

Sex differences in cardiovascular and subjective stress reactions: prospective evidence in a realistic military setting.

Evidence points to heightened physiological arousal in response to acute stress exposure as both a prospective indicator and a core characteristic of posttraumatic stress disorder (PTSD). Because females may be at higher risk for PTSD development, it is important to evaluate sex differences in acute stress reactions. This study characterized sex differences in cardiovascular and subjective stress reactions among military survival trainees. One hundred and eighty-five military members (78% males) were studied before, during, and 24 h after stressful mock captivity. Cardiovascular (heart rate [HR], systolic blood pressure [SBP], diastolic blood pressure [DBP]) and dissociative states were measured at all three time points. Psychological impact of mock captivity was assessed during recovery. General linear modeling with repeated measures evaluated sex differences for each cardiovascular endpoint, and causal steps modeling was used to explore interrelationships among sex, cardiovascular reactions and psychological impact of mock captivity. Although females had lower SBP than males at all three time points, the difference was most pronounced at baseline and during stress. Accordingly, females showed greater residual elevation in SBP during recovery. Females had lower DBP at all three time points. In addition, females reported greater psychological impact of mock captivity than males. Exploratory causal steps modeling suggested that stress-induced HR may partially mediate the effect of sex on psychological impact of mock captivity. In conclusion, this study demonstrated sex-specific cardiovascular stress reactions in military personnel, along with greater psychological impact of stress exposure in females. This research may elucidate sex differences in PTSD development.

Spontaneous and deliberate dissociative states in military personnel: are such states helpful?

This study explored distinctions between spontaneous and deliberate dissociative states in 335 military personnel exposed to stressful survival training. Participants completed the Clinician-Administered Dissociative States Scale (CADSS) after a stressful mock-captivity event. They were also asked to indicate whether the dissociative experiences just happened (i.e., spontaneous), or whether they chose to have them happen (i.e., deliberate); and whether they appraised the dissociative experience as helpful (i.e., facilitative) or hurtful (i.e., debilitative) to their ability to cope with the stressful event. A majority (95.4%) endorsed dissociative states during stress. More than half (57.4%) described dissociative experiences as spontaneous, 13.0% as deliberate, and 29.5% endorsed neither. In Special Forces soldiers only, those who endorsed facilitative dissociation exhibited higher total CADSS scores than those who endorsed debilitative dissociation. Seventy-three percent of spontaneous dissociators described the experience as debilitative to coping with stress; conversely, 76% of deliberate dissociators said these experiences facilitated coping with stress. Individuals with prior trauma exposure tended to appraise dissociative states as more debilitative to coping. This research may enhance the fidelity of studies of dissociation constructs and may offer pivot points for prevention and treatment of stress-related disorders.

Efficacy of forensic statement analysis in distinguishing truthful from deceptive eyewitness accounts of highly stressful events.

Laboratory-based detecting deception research suggests that truthful statements differ from those of deceptive statements. This nonlaboratory study tested whether forensic statement analysis (FSA) methods would distinguish genuine from false eyewitness accounts about exposure to a highly stressful event. A total of 35 military participants were assigned to truthful or deceptive eyewitness conditions. Genuine eyewitness reported truthfully about exposure to interrogation stress. Deceptive eyewitnesses studied transcripts of genuine eyewitnesses for 24 h and falsely claimed they had been interrogated. Cognitive Interviews were recorded, transcribed, and assessed by FSA raters blind to the status of participants. Genuine accounts contained more unique words, external and contextual referents, and a greater total word count than did deceptive statements. The type-token ratio was lower in genuine statements. The classification accuracy using FSA techniques was 82%. FSA methods may be effective in real-world circumstances and have relevance to professionals in law enforcement, security, and criminal justice.

Baseline burnout symptoms predict visuospatial executive function during survival school training in special operations military personnel.

Burnout symptoms, which are characterized by exhaustion, cynicism, and a reduced sense of professional efficacy, may deleteriously affect cognitive function in military personnel. A total of 32 U.S. Military Special Operations personnel enrolled in Survival School completed measures of trauma history, dissociation, and burnout before training. They then completed the Groton Maze Learning Test (GMLT), a neuropsychological measure of integrative visuospatial executive function during three field-based phases of Survival School-enemy evasion, captivity/interrogation, and escape/release from captivity. Lower pre-training perceptions of professional efficacy were associated with reduced executive function during all of the field-based phases of Survival School, even after adjustment for years of education, cynicism, and baseline GMLT scores. Magnitudes of decrements in executive function in Marines with low efficacy relative to those with high efficacy increased as training progressed and ranged from .58 during enemy evasion to .99 during escape/release from captivity. Pre-training perceptions of burnout may predict visuospatial executive function during naturalistic training-related stress in military personnel. Assessment of burnout symptoms, particularly perceptions of professional efficacy, may help identify military personnel at risk for stress-related executive dysfunction.

Sleep quality in treatment-seeking veterans of Operations Enduring Freedom and Iraqi Freedom: the role of cognitive coping strategies and unit cohesion.

OBJECTIVE: Sleep difficulties are common in individuals exposed to stress or trauma, and maladaptive cognitive coping strategies, such as worry and fear of losing vigilance, as well as low social support, may further impair sleep quality. This study examined the severity and correlates of sleep difficulties in a sample of treatment-seeking veterans of Operations Enduring Freedom and Iraqi Freedom (OEF-OIF). METHOD: A total of 167 OEF-OIF veterans seeking behavioral or primary care services completed a questionnaire containing measures of sleep quality, combat exposure, psychopathology, fear of loss of vigilance, cognitive coping strategies, and unit and postdeployment social support within 1 year of returning from deployment. RESULTS: Mean Pittsburgh Sleep Quality Inventory scores in the full sample were indicative of severely impaired sleep. Posttraumatic stress disorder (PTSD) was associated with increased sleep difficulties, most notably sleep disturbances, daytime dysfunction, and sleep quality. Hierarchical regression analysis in the full sample revealed that PTSD symptoms and scores on measures of worry and fear of loss of vigilance were positively associated with sleep difficulties and that scores on a measure of unit member support were negatively associated with sleep difficulties. Among veterans with PTSD, fear of loss of vigilance was positively associated with sleep difficulties and cognitive distraction and unit member support were negatively associated with sleep difficulties. CONCLUSIONS: Treatment-seeking OEF-OIF veterans report severe sleep difficulties, with more pronounced impairment in veterans with PTSD. The results of this study suggest that interventions to mitigate worry and fear of loss of vigilance and to enhance perceived unit member support may be helpful in reducing sleep difficulties following return from deployment in this population.

Posttraumatic growth in Veterans of Operations Enduring Freedom and Iraqi Freedom.

OBJECTIVE: A growing body of research has examined the prevalence and correlates of psychopathology, mild traumatic brain injury, and related problems in Veterans of Operations Enduring Freedom and Iraqi Freedom (OEF-OIF). While these studies help characterize the deleterious effects of combat, no known study has examined factors that may enhance posttraumatic growth or positive changes experienced as a result of combat in this population. METHOD: A total of 272 predominantly older Reservist/National Guard OEF-OIF Veterans completed an anonymous mail survey that assessed combat exposure, psychopathology, psychosocial functioning, social support, and posttraumatic growth. RESULTS: Seventy-two percent of the sample endorsed a significant degree of posttraumatic growth in at least one of the areas assessed, the most common of which were changing priorities about what is important in life (52.2%), being able to better appreciate each day (51.1%), and being better able to handle difficulties (48.5%). Hierarchical regression analysis revealed that younger age, greater posttraumatic stress disorder (PTSD) symptoms, and increased perceptions of unit member support and effort/perseverance were significantly associated with posttraumatic growth. Respondents with PTSD scored higher on an overall measure of posttraumatic growth and on items reflecting appreciation of life and personal strength. LIMITATIONS: This study is limited by a relatively low survey return rate and employment of an abbreviated measure of posttraumatic growth. CONCLUSIONS: Results of this study suggest that interventions to bolster unit member support and to enhance perceptions of effort and perseverance may help promote posttraumatic growth in OEF-OIF Veterans.

Psychosocial buffers of traumatic stress, depressive symptoms, and psychosocial difficulties in veterans of Operations Enduring Freedom and Iraqi Freedom: the role of resilience, unit support, and postdeployment social support.

BACKGROUND: Little research has examined the role of protective factors such as psychological resilience, unit support, and postdeployment social support in buffering against PTSD and depressive symptoms, and psychosocial difficulties in veterans of Operations Enduring Freedom (OEF) and Iraqi Freedom (OIF). MATERIALS AND METHODS: A total of 272 OEF/OIF veterans completed a survey containing PTSD and depression screening measures, and questionnaires assessing resilience, social support, and psychosocial functioning. RESULTS: Lower unit support and postdeployment social support were associated with increased PTSD and depressive symptoms, and decreased resilience and psychosocial functioning. Path analyses suggested that resilience fully mediated the association between unit support and PTSD and depressive symptoms, and that postdeployment social support partially mediated the association between PTSD and depressive symptoms and psychosocial functioning. LIMITATIONS: Generalizability of results is limited by the relatively low response rate and predominantly older and reserve/National Guard sample. CONCLUSIONS: These results suggest that interventions designed to bolster unit support, resilience, and postdeployment support may help protect against traumatic stress and depressive symptoms, and improve psychosocial functioning in veterans.

Baseline dissociation and prospective success in Special Forces Assessment and Selection.

INTRODUCTION: Although dissociation at the time of trauma (peritraumatic dissociation) has been shown to predict the development of posttraumatic stress disorder (PTSD), it is not yet known whether the tendency to dissociate under nonstressful circumstances (i.e., at baseline) can also serve as a predictor of vulnerability to stress in healthy individuals. METHOD: Baseline symptoms of dissociation (CADSS) were assessed in 774 active duty male Soldiers enrolled in Special Forces Assessment and Selection (SFAS). RESULTS: Soldiers who endorsed experiencing any symptoms of dissociation at baseline were significantly less likely to be successful in SFAS. The greater the number of symptoms of dissociation endorsed at baseline, the greater the likelihood of failure. DISCUSSION: These data explain our earlier findings of fewer symptoms of dissociation in elite troops and may have relevance for the selection and hiring of personnel for nonmilitary, at-risk professions. Better screening may lead to improved primary intervention strategies, better job placement, and lowered risk of PTSD.

Psychosocial buffers of traumatic stress, depressive symptoms, and psychosocial difficulties in veterans of Operations Enduring Freedom and Iraqi Freedom: the role of resilience, unit support, and postdeployment social support.

BACKGROUND: Little research has examined the role of protective factors such as psychological resilience, unit support, and postdeployment social support in buffering against PTSD and depressive symptoms, and psychosocial difficulties in veterans of Operations Enduring Freedom (OEF) and Iraqi Freedom (OIF). MATERIALS AND METHODS: A total of 272 OEF/OIF veterans completed a survey containing PTSD and depression screening measures, and questionnaires assessing resilience, social support, and psychosocial functioning. RESULTS: Lower unit support and postdeployment social support were associated with increased PTSD and depressive symptoms, and decreased resilience and psychosocial functioning. Path analyses suggested that resilience fully mediated the association between unit support and PTSD and depressive symptoms, and that postdeployment social support partially mediated the association between PTSD and depressive symptoms and psychosocial functioning. LIMITATIONS: Generalizability of results is limited by the relatively low response rate and predominantly older and reserve/National Guard sample. CONCLUSIONS: These results suggest that interventions designed to bolster unit support, resilience, and postdeployment support may help protect against traumatic stress and depressive symptoms, and improve psychosocial functioning in veterans.

Relationships among plasma dehydroepiandrosterone and dehydroepiandrosterone sulfate, cortisol, symptoms of dissociation, and objective performance in humans exposed to underwater navigation stress.

BACKGROUND: A growing body of research has provided evidence that dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEAS) are involved in an organism's response to stress and that it may provide beneficial behavioral and neurotrophic effects. METHODS: This study investigated plasma DHEA and DHEAS, cortisol, psychological symptoms of dissociation, and military performance in 41 healthy active duty subjects enrolled in the military Combat Diver Qualification Course (CDQC). RESULTS: Baseline values of DHEA and DHEAS were significantly and positively predictive of superior performance in the underwater navigation exam; in addition, DHEA and DHEAS were significantly and negatively related to stress-induced symptoms of dissociation during performance of the task. Similarly, participants who reported fewer symptoms of dissociation exhibited superior military performance and increased levels of DHEA after the test. CONCLUSIONS: These data provide prospective, empiric evidence that DHEA and DHEAS are associated with superior stress tolerance, fewer symptoms of dissociation, and superior, objectively assessed, military performance.

Effect of carbohydrate administration on recovery from stress-induced deficits in cognitive function: a double-blind, placebo-controlled study of soldiers exposed to survival school stress.

OBJECTIVE: The goal of this project was to evaluate the effects of energy supplementation, as liquid carbohydrate (CHO), on facilitating recovery of cognitive function in soldiers who have been exposed to sustained psychological and physical stress during Survival School Training. PROJECT DESIGN: A double-blind, placebo-controlled design was used. Healthy, male volunteers attending survival training were recruited for participation in the study. At the conclusion of the mock captivity phase of survival training and before a recovery night of sleep, subjects participated in cognitive testing. After this, subjects were randomly assigned to one of three treatment groups. Subjects received either a 6% CHO (35.1 kJ/kg), 12% CHO (70.2 kJ/kg), or placebo beverage in four isovolemic doses. In the morning of the following day, all subjects participated in a second assessment of cognitive functioning. RESULTS: Compared to subjects who received placebo, those who received supplemental CHO beverages exhibited significantly improved performance on a complex cognitive task (i.e., Stroop Test) involving concentration effectiveness associated with selective attention and response inhibition. No differences were observed on a variety of cognitive tasks of lesser complexity. DISCUSSION: These data suggest nutritional interventions enhance the rapid recovery of complex cognitive functions impaired by exposure to significant or sustained stressful conditions. In addition to enhancing speed of recovery of function between operational intervals, the current data suggest that dietary supplement strategies may hold promise for enhancing field performance and a capacity to assist in sustaining operations by military personnel over time.

Baseline dissociation and prospective success in special forces assessment and selection.

INTRODUCTION: Although dissociation at the time of trauma (peritraumatic dissociation) has been shown to predict the development of posttraumatic stress disorder (PTSD), it is not yet known whether the tendency to dissociate under nonstressful circumstances (i.e., at baseline) can also serve as a predictor of vulnerability to stress in healthy individuals. METHOD: Baseline symptoms of dissociation (CADSS) were assessed in 774 active duty male soldiers enrolled in Special Forces Assessment and Selection (SFAS). RESULTS: Soldiers who endorsed experiencing any symptoms of dissociation at baseline were significantly less likely to be successful in SFAS. The greater the number of symptoms of dissociation endorsed at baseline, the greater the likelihood of failure. DISCUSSION: These data explain our earlier findings of fewer symptoms of dissociation in elite troops and may have relevance for the selection and hiring of personnel for nonmilitary, at-risk professions. Better screening may status (positively or negatively) in SFAS. Of the 794 SFAS candidates who were given the study recruitment speech, 774 candidates enrolled in the study. Thus, the refusal rate was three percent. Information on the 20 individuals who refused to participate in the study was not available to the research team. PARTICIPANTS: Of the 794 candidates approached, 774 (97%) active duty male soldiers (mean age 26, SD=4) agreed to participate in the study. All participants were enrolled in a US Army SFAS program. The participants' mean years of service in the Army was 4.9 (SD=3.2). Two-hundred eighty soldiers (36%) were married, 403 (52%) soldiers were single, and 86 (11%) soldiers were divorced. Eighty-six percent or 677 candidates were enlisted and 110 (14%) were officers. PROCEDURE: After providing informed consent, participants completed the self-report portion of the Clinician Administered Dissociative Symptom Scale (CADSS). The CADSS is a reliable, valid, self-report instrument designed to assess state symptoms of dissociation in response to a specified stressor.(14) Subjects were instructed to complete the CADSS using the week previous to enrollment in the course as their reference point. Subjects were instructed to inform the research team (orally and in writing) if during the previous week they had experienced any traumatic or highly stressful events. We did not include the clinician-observer component of the CADSS given the low intercorrelation coefficients for this component. After completing the CADSS, participants commenced participation in SFAS. DATA ANALYSIS: In order to test the hypothesis that symptoms of dissociation would be significantly related to success or failure in SFAS, the following variables were created: total CADSS scores (the sum of individual CADSS items); classification scores indicating whether or not subjects reported symptoms of dissociation at baseline (1=yes; 0=no); and two additional classification scores designed to classify subjects in a binary fashion based on whether or not their CADSS total score was greater than, at, or below a specified value (less than 5; equal to, or greater than, 5; less than 11; equal to or greater than 11). These classification cut-off points were selected based on the distribution of responses from subjects in this study and on the mean pre-stress CADSS dissociation scores noted in our previous studies.(15) Chi-squared analyses were performed to test whether subjects endorsing baseline symptoms of dissociation (any, greater than 5 points, greater than 11 points) were more likely to fail SFAS compared to peers who did not report such symptoms. Receiver operator characteristics (ROC) curvesROC curves were created by using the CADSS baseline total score (the test variable) in order to predict outcome in the SFAS program (the state variable, where 1= failed SFAS). ROC graphs were created for the group as a whole and for the sub-group of subjects whose CADSS score was 1 or greater. For both ROC graphs, the area under the curve as well as coordinate points for the curve were calculated (SPSS 11.5). The null hypothesis assumption was that the true area under the curve equals 0.5. With regard to the parameters for the standard distribution of error, the distribution assumption was nonparametric and the confidence interval 95 percent.(16) Although this method is also a regression model, it offers an advantage over the logistic regression format in that a classification table corresponding to specific scores on the CADSS and to the likelihood of success or failure in the course is possible.