Non-patient Participants Research Articles

Automatic Detection of Cognitive Impairment with Virtual Reality.

Cognitive impairment features in neuropsychiatric conditions and when undiagnosed can have a severe impact on the affected individual's safety and ability to perform daily tasks. Virtual Reality (VR) systems are increasingly being explored for the recognition, diagnosis and treatment of cognitive impairment. In this paper, we describe novel VR-derived measures of cognitive performance and show their correspondence with clinically-validated cognitive performance measures. We use an immersive VR environment called VStore where participants complete a simulated supermarket shopping task. People with psychosis (k=26) and non-patient controls (k=128) participated in the study, spanning ages 20-79 years. The individuals were split into two cohorts, a homogeneous non-patient cohort (k=99 non-patient participants) and a heterogeneous cohort (k=26 patients, k=29 non-patient participants). Participants' spatio-temporal behaviour in VStore is used to extract four features, namely, route optimality score, proportional distance score, execution error score, and hesitation score using the Traveling Salesman Problem and explore-exploit decision mathematics. These extracted features are mapped to seven validated cognitive performance scores, via linear regression models. The most statistically important feature is found to be the hesitation score. When combined with the remaining extracted features, the multiple linear regression model resulted in statistically significant results with R2 = 0.369, F-Stat = 7.158, p(F-Stat) = 0.000128.

Development and validation of a machine learning-based vocal predictive model for major depressive disorder

BackgroundVariations in speech intonation are known to be associated with changes in mental state over time. Behavioral vocal analysis is an algorithmic method of determining individuals' behavioral and emotional characteristics from their vocal patterns. It can provide biomarkers for use in psychiatric assessment and monitoring, especially when remote assessment is needed, such as in the COVID-19 pandemic.The objective of this study was to design and validate an effective prototype of automatic speech analysis based on algorithms for classifying the speech features related to MDD using a remote assessment system combining a mobile app for speech recording and central cloud processing for the prosodic vocal patterns. MethodsMachine learning compared the vocal patterns of 40 patients diagnosed with MDD to the patterns of 104 non-clinical participants. The vocal patterns of 40 patients in the acute phase were also compared to 14 of these patients in the remission phase of MDD. ResultsA vocal depression predictive model was successfully generated. The vocal depression scores of MDD patients were significantly higher than the scores of the non-patient participants (p < 0.0001). The vocal depression scores of the MDD patients in the acute phase were significantly higher than in remission (p < 0.02). LimitationsThe main limitation of this study is its relatively small sample size, since machine learning validity improves with big data. ConclusionsThe computerized analysis of prosodic changes may be used to generate biomarkers for the early detection of MDD, remote monitoring, and the evaluation of responses to treatment.

Identifying outcome measures for atrial fibrillation value-based contracting using the Delphi method.

Value-based contracts that tie payments for pharmaceuticals to predefined outcomes aim to promote value through shared risk and aligned incentives between manufacturers and payers. We conducted a Delphi study among diverse stakeholders (patients, providers, payers, pharmacy benefits managers, pharmaceutical company representatives) to identify top meaningful outcomes for inclusion in value-based contracts for atrial fibrillation medications. The final panel (n=55) rated the importance of each outcome on a 5-point Likert scale and selected their top 3 most meaningful outcomes. Non-patient participants rated the feasibility of collecting each outcome on a 5-point Likert scale. Consensus was defined as ≥75% agreement (Likert scores ≥4/5 or selection of an outcome as most meaningful). Differences between stakeholder groups were examined using Fisher's Exact Test. Consensus was achieved for importance of 10 outcomes (Likert scale), where "preventing stroke or mini-stroke" reached 100% agreement (55/55). Eighty-one percent (44/54) of participants selected "preventing stroke or mini-stroke" as the most meaningful outcome (rank order question). The measures rated as most feasibly collected were "reducing hospitalizations" (97%, 36/37) followed by "preventing stroke or mini-stroke" and "reducing emergency department visits" (both 92%, 34/37). There were statistically significant differences between patients and non-patients [0% (0/17) vs 22% (8/37), P=0.047] and patients and providers [0% (0/17) vs 39% (7/18), P=0.008] in selection of "improving health-related quality of life" as a most meaningful outcome. These findings will inform the design of atrial fibrillation value-based pharmaceutical contracts and provide additional insight into preferences for outcomes which could be used to improve the quality of atrial fibrillation care.

Stigma May Exacerbate Disproportionately Low Guideline-Concordant Treatment Rates for Patients With Advanced-Stage Lung Cancer in the United States

Stigma May Exacerbate Disproportionately Low Guideline-Concordant Treatment Rates for Patients With Advanced-Stage Lung Cancer in the United States

Evaluation of sagittal condylar guidance angles using computerized pantographic tracings, protrusive interocclusal records, and 3D-CBCT imaging techniques for oral rehabilitation.

The goal of registering the condylar guidance is to recreate the patient's occlusion as exactly as possible on the articulator, and is therefore essential for successful prosthodontic rehabilitation. Clinical, radiographic, and pantographic methods are used to determine sagittal condylar guidance angles (SCGAs). These methods generate different angles in the same patients. The present study is the first disquisition to evaluate and correlate SCGAs determined by the use of pantographic tracing (PT), protrusive records (PR), and radiographic (CBCT) techniques. The condylar guidance was measured using PT, PR, and CBCT imaging techniques in 23 nonpatient participants aged between 18 and 30 years irrespective of sex. PT was recorded using Cadiax® Compact system, a computerized recorder of SCGAs. PR was obtained using polyvinyl siloxane bite registration material, transferred to a semiadjustable articulator (Denar Mark II, Whip Mix Corp., USA) using facebow transfer (Denar Mark II, Whip Mix Corp., USA) and CR records, to determine SCGAs. Images of the mid-facial region were obtained using CBCT scan for 3D reconstruction. The angle formed between Frankfort horizontal plane (FHP) and a line extending from the most supero-anterior point on the glenoid fossa to the most convex point on the apex of articular eminence (AE) was measured to obtain SCGAs. The mean left and right SCGAs were as follows: PT (34.42° and 33.93°, respectively), PR (32.14° and 31.82°), and CBCT (38.96° and 38.12°). The Pearson coefficients for the correlations with PT and PR on the left and right sides were 0.899 and 0.907, respectively, while it was 0.911 and 0.934, and 0.842 and 0.874 from PT and CBCT, and PR and CBCT, respectively. Strong correlations were found between SCGAs obtained using PT, PR, and CBCT techniques.

Identifying Outcome Measures for Type 2 Diabetes Value-Based Contracting Using the Delphi Method.

Value-based contracts (VBCs) between payers and pharmaceutical manufacturers link drug payments to predefined performance measures and require shared risk between both entities. It is unclear how outcome measures were selected in previously reported VBCs, and many VBCs have focused on surrogate endpoints often used in the conduct of clinical trials, which may not be valued by or of importance to patients. To identify outcome measures that are meaningful to key stakeholders and feasibly measured to inform VBCs for diabetes medications. We conducted a modified Delphi survey to incorporate views from patients (n = 9), endocrinologists (n = 5), primary care physicians (n = 4), payers (n = 3), pharmacy benefit managers (n = 3), and pharmaceutical company representatives (n = 2). A list of 12 diabetes-related outcome measures was generated from the literature and consultations with subject matter experts. Participants rated the importance of each outcome on a 5-point Likert scale and selected the 3 most meaningful outcomes. Nonpatient participants then used a Likert scale to rate the feasibility of collecting each outcome. Consensus was defined as ≥ 75% agreement on the importance and feasibility of an outcome (Likert scores 4 or 5 or selection of an outcome as most meaningful). A 2-sample test of proportions was performed to examine differences between patient and nonpatient stakeholder rankings of outcomes. All 12 outcomes reached consensus for importance on the Likert scale. The measure "reducing risk of heart attacks" was the most meaningful outcome (84%), while "reducing A1c levels" ranked second (68%). The 2 measures rated as most feasibly collected were "reducing A1c levels" and "reducing risk of hospitalizations from diabetes" (93.8% each). The measures "weight loss," "reducing risk of diabetes-related kidney disease," "reducing risk of emergency room visits from diabetes," and "reducing risk of diabetes-related amputations and foot ulcers" also reached consensus for feasibility. There were statistically significant differences between patient and nonpatient stakeholders in the selection of "reducing A1c levels" (37.5% vs. 82.3%, respectively; P = 0.03) and "reducing risk of diabetes-related kidney disease" (50.0% vs. 11.8%, respectively; P = 0.03) as most meaningful outcomes. The measures "reducing risk of heart attacks" and "reducing A1c levels" were identified as top priority diabetes outcome measures. Express Scripts provided research funding for this study to the UPMC Center for Value-Based Pharmacy Initiatives. Henderson is employed by Express Scripts and was involved in the conception and design of the study and manuscript approval. The other authors are employed by the UPMC Center for Value-Based Pharmacy Initiatives and have nothing to disclose.

Generalization of Conscious Fear Is Positively Correlated with Anxiety, but Not with Depression.

Generalization of learned fear has been considered to be critical for our survival. Patients with anxiety problems show overgeneralization of learned fear, as reflected by defensive physiological responses to harmless stimuli. Together with these physiological responses, conscious feeling of fear is a seminal part of emotional process that is directly related to the suffering of anxiety patients. However, the effect of anxiety on the generalization of conscious feeling remains unclear. We thus focused on the question whether the generalization of conscious feeling of fear depends on individual anxiety level in nonpatient participants. To address this question, we developed a fear generalization paradigm using natural scene images. We found that subjective feeling of fear was generalized to similar stimuli with the conditioned stimuli (CS), and that this generalization of conscious fear was positively correlated with the level of individual anxiety. Anxiety and depression frequently co-occur, but the individual depression level was not correlated with the fear generalization. These suggest that individual anxiety level mainly affects the generalization of conscious fear.

A Protocol for a Feasibility and Acceptability Study of a Participatory, Multi-Level, Dynamic Intervention in Urban Outreach Centers to Improve the Oral Health of Low-Income Chinese Americans.

While the US health care system has the capability to provide amazing treatment of a wide array of conditions, this care is not uniformly available to all population groups. Oral health care is one of the dimensions of the US health care delivery system in which striking disparities exist. More than half of the population does not visit a dentist each year. Improving access to oral health care is a critical and necessary first step to improving oral health outcomes and reducing disparities. Fluoride has contributed profoundly to the improved dental health of populations worldwide and is needed regularly throughout the life course to protect teeth against dental caries. To ensure additional gains in oral health, fluoride toothpaste should be used routinely at all ages. Evidence-based guidelines for annual dental visits and brushing teeth with fluoride toothpaste form the basis of this implementation science project that is intended to bridge the care gap for underserved Asian American populations by improving access to quality oral health care and enhancing effective oral health promotion strategies. The ultimate goal of this study is to provide information for the design and implementation of a randomized controlled trial of a participatory, multi-level, partnered (i.e., with community stakeholders) intervention to improve the oral and general health of low-income Chinese American adults. This study will evaluate the feasibility and acceptability of implementing a partnered intervention using remote data entry into an electronic health record (EHR) to improve access to oral health care and promote oral health. The research staff will survey a sample of Chinese American patients (planned n = 90) screened at three outreach centers about their satisfaction with the partnered intervention. Providers (dentists and community health workers), research staff, administrators, site directors, and community advisory board members will participate in structured interviews about the partnered intervention. The remote EHR evaluation will include group adaptation sessions and workflow analyses via multiple recorded sessions with research staff, administrators, outreach site directors, and providers. The study will also model knowledge held by non-patient participants to evaluate and enhance the partnered intervention for use in future implementations.

The relationship between personality disorder traits and reactive versus proactive motivation for aggression

There is a strong link between personality disorders (PDs) and aggression. This is reflected in high prevalence rates of PD diagnoses in forensic samples, and in several diagnostic criteria of PDs directly referring to elevated levels of aggression. Aggression can stem from two distinct types of motivation; reactive or impulsive aggression that serves as a defensive reaction to provocation, and proactive or premeditated aggression used to gain extrinsic benefits. Although some clinical conditions like antisocial, borderline, and narcissistic PDs or PD traits, have been empirically linked to reactive and/or proactive aggression, the current study pioneers assessing the relationship between reactive and proactive aggression and traits of all 10 PDs. A mixed sample of patient and non-patient (N=238) participants were administered with the SCID II to assess the level of PD traits; they also completed the Reactive Proactive Questionnaire to determine levels of reactive and proactive aggression. Results showed that paranoid PD traits were positively related to reactive aggression, whereas proactive aggression was uniquely related to antisocial PD traits. This highlights the importance of differentiating between distinct motivations for aggression in PD samples.

In the wake of a possible mistake: Security motivation, checking behavior, and OCD

Background and objectivesIn previous experiments, OCD washers did not differ significantly from controls in their initial level of activation in response to the potential threat of contamination; however, they were less able to reduce their activation by engaging in hand-washing, suggesting that the key problem in OCD is a faulty stopping mechanism. The main objectives of the present experiments were to develop a similar experimental paradigm for investigating checking behavior, and to use it to test the hypothesis that a faulty stopping mechanism also underlies OCD checking. MethodsParticipants sorted pills under the guise of beta testing a new medication system and then were given suggestions of the possibility of having made mistakes with potentially serious consequences. Later, participants engaged in a 90-s checking period and an unlimited period of checking. At baseline and three other times during the experiment, security motivation was measured with respiratory sinus arrhythmia (RSA) and subjective ratings of confidence. Experiment 1 established the parameters of the paradigm in non-patient participants, and Experiment 2 contrasted OCD checkers with OCD washers and non-patients. ResultsResults for both subjective and physiological measures of security motivation closely replicated previous findings for washing behavior. Groups did not differ significantly in initial activation, but the OCD checkers were unable to reduce their activation by engaging in period of checking that was ample for returning controls to baseline. LimitationsThe sample size for the patient groups was modest. ConclusionsThese results lend further support to the security-motivation theory of OCD.

Low temporal precision for high impulsive individuals

Previous studies have shown that impulsive people perceive time differently from non-impulsive people. However, these studies either recruited participants from the clinical population or used impulsive behavior (rather than impulsivity trait itself) as the index of impulsivity. We investigated the relationship between time perception and self-report impulsivity trait (measured by the Barratt Impulsiveness Scale; BIS-11) in non-patient participants. We used the oddball paradigm to measure subjective duration and discrimination precision in high- and low-impulsive groups. Results show that high impulsive participants’ discrimination precision was lower than low impulsive participants (Experiment 1). The possibility that this is due to high impulsive participants having weaker attentional maintenance of the task was excluded (Experiment 2). By removing potentially confounding factors that existed in previous studies, our results demonstrate a more convincing relationship between temporal precision and the impulsivity trait in healthy participants.

The Musculoskeletal Function Assessment

Historically, outcomes in orthopedic surgery had been assessed using clinical scores. Currently, functional outcome has become the important measure. The Musculoskeletal Function Assessment is valid and reliable, patient-assessed health status questionnaire used by physicians to determine outcomes in patients with musculoskeletal disorders. Reference values for outcomes instruments establish a baseline for evaluating patient function. What have come to be accepted as reference values for the Musculoskeletal Function Assessment were published in 1999 from a small nonpatient sample. The purpose of this prospective study was to establish normal reference values for the Musculoskeletal Function Assessment for healthy adults for a larger, randomly selected population. This is a prospective, observational study. Musculoskeletal Function Assessment data were collected from subjects within a 100-mile radius of our midwestern city. The Musculoskeletal Function Assessment questionnaire was administered to 406 participants randomly selected from public data. Data were collected over a 2-year period. There were 215 male and 191 female responders. Stratification criteria included gender, age (18-35, 36-55, and 56-89 years), and body mass index. There were 58 in age group 28-35 years, 102 in age group 36-55 year, and 246 in age group 56-89 years. The primary study measure was to compare Musculoskeletal Function Assessment scores for healthy nonpatient participants in the Midwest to the nonpatient data originally published in 1999. Musculoskeletal Function Assessment values were significantly higher, indicating poorer function, in all categories and demographics when compared with the previously reported data. This prospective study shows that our normal population's baseline function is significantly poorer than previously reported. In addition to indicating that the previously reported information possibly was incorrect, our findings suggest that temporal and/or geographic conditions may influence Musculoskeletal Function Assessment normative data. Therefore, assessing functional outcome may be a dynamic rather than a static process, requiring periodic updating to reestablish normative data.

The Development and Validation of the Beliefs about Paranoia Scale (Short Form)

This study reports the development and revision of the Beliefs about Paranoia Scale (BaPS), a self-report measure to assess metacognitive beliefs about paranoia in non-patients. We aimed to confirm the factor structure of a revised 50-item version of the measure and test the specific hypotheses that positive beliefs about paranoia would predict frequency of paranoia, and that negative beliefs about paranoia would predict distress associated with paranoia. 185 non-patient participants completed questionnaires assessing beliefs about paranoia, thought control, self-consciousness, anxiety, depression and paranoia. The results showed that the original four-factor solution could not be replicated. Instead a three-factor solution comprising Negative Beliefs about Paranoia, Paranoia as a Survival Strategy, and Normalizing Beliefs was developed. The revised 18-item measure showed good internal consistency. Stepwise regression analysis showed that, BaPS-negative beliefs accounted for 34% of the variance with R2 of 0.339, with a multiple R of 0.585 in relation to frequency of paranoia. In relation to distress arising from paranoia, stepwise regression analysis showed that BaPS-negative beliefs accounted for 34% of the variance with R2 of 0.339, with a multiple R of 0.585. In both analyses, BaPS-Survival strategy showed a small but significant incremental increase in the variance accounted for in the overall model. These findings suggest that a metacognitive approach to the conceptualization of paranoia as a strategy for managing interpersonal threat may have some utility. The clinical implications of the findings are also discussed.

Memory for Pain? A Comparison of Nonexperiential Estimates and Patients’ Reports of the Quality and Intensity of Postoperative Pain

Prior research has questioned the extent to which postoperative retrospective ratings of acute pain actually reflect memory of that pain. To investigate this issue, pain ratings provided by patients who had undergone vascular surgery were compared with estimates of this pain provided by 2 groups of healthy, nonpatient participants with no personal experience of the surgery. Patient participants rated postoperative pain while actually experiencing it and again 4 to 6 weeks after surgery. Nonpatient groups read either a comprehensive information leaflet describing postoperative pain after vascular surgery, or a short general information leaflet about the surgery and provided 2 estimates of the likely nature of the pain, 4 to 6 weeks apart. Compared with patients, both nonpatient groups overestimated pain severity, and nonpatients provided with the comprehensive information leaflet were less consistent in their estimates compared with the other 2 groups. However, qualitative descriptions of the pain provided by the 3 groups shared many similarities. Our findings highlight limitations of inferring pain memory accuracy by comparing ratings given while in pain with those provided retrospectively and demonstrate the need to consider the phenomenological awareness accompanying recollections of prior pain events to advance our understanding of memory for pain. The observed similarities between pain ratings made by individuals who have experienced a particular pain and estimates made by those without personal experience question whether retrospective pain ratings can be assumed to reflect memory of that pain. The need to adopt new approaches to assess memory for pain is highlighted.

Assessing the Benefit of Radiation Therapy After Breast-Conserving Surgery for Ductal Carcinoma-In-Situ

To assess women's preferences regarding the trade-off between the risks and benefits of treatment with radiation therapy (RT) after breast-conserving surgery (BCS) for ductal carcinoma-in-situ (DCIS). Utilities were obtained from 120 patients and 210 nonpatients for eight relevant health states using standard gambles. Differences in utilities obtained from patient and nonpatient participants between health states were relatively similar. Reduction in the likelihood of local recurrence associated with RT did not result in higher utilities. Utilities for noninvasive recurrence were only lower after initial treatment with RT. Patient and nonpatient participants had the lowest utilities for invasive local recurrence, regardless of initial treatment or manner of salvage therapy. When comparing patient and nonpatient utilities directly, patients had higher utility for being without recurrence after initial RT and lower utility for invasive recurrence salvaged by mastectomy after initial BCS alone. None of the clinical or sociodemographic factors examined explained more than 5% of the variability in the patients' or nonpatients' utilities or their differences. The principal benefit associated with adding RT to BCS for DCIS seems to be its ability to reduce invasive recurrences.

The Beliefs about Paranoia Scale: Preliminary Validation of a Metacognitive Approach to Conceptualizing Paranoia

This study reports the development of a self-report measure to assess metacognitive beliefs about paranoia in non-patients. We aimed to test the specific hypotheses that positive beliefs about paranoia would predict frequency of paranoia, and that negative beliefs about paranoia would predict distress associated with delusional ideation. Three-hundred and seventeen non-patient participants were asked to complete questionnaires assessing beliefs about paranoia, paranoia, dimensions of delusional ideation and trait anxiety. The results showed that four empirically distinct subscales were measured by the beliefs about paranoia scale (negative beliefs about paranoia, beliefs about paranoia as a survival strategy, general positive beliefs and normalising beliefs). The scales possessed acceptable internal consistency and were associated with the measures of paranoia, delusional ideation and anxiety. Consistent with predictions, it was found that beliefs about paranoia as a survival strategy were associated with frequency of paranoia, and negative beliefs were associated with distress associated with delusional ideation. These findings suggest that a metacognitive approach to the conceptualization of paranoia as a strategy for managing interpersonal threat may have some utility. The clinical implications of the findings are also discussed.

Anhedonia and illness chronicity measured over twenty years of schizophrenic illness

In previous experiments, OCD washers did not differ significantly from controls in their initial level of activation in response to the potential threat of contamination; however, they were less able to reduce their activation by engaging in hand-washing, suggesting that the key problem in OCD is a faulty stopping mechanism. The main objectives of the present experiments were to develop a similar experimental paradigm for investigating checking behavior, and to use it to test the hypothesis that a faulty stopping mechanism also underlies OCD checking.Participants sorted pills under the guise of beta testing a new medication system and then were given suggestions of the possibility of having made mistakes with potentially serious consequences. Later, participants engaged in a 90-s checking period and an unlimited period of checking. At baseline and three other times during the experiment, security motivation was measured with respiratory sinus arrhythmia (RSA) and subjective ratings of confidence. Experiment 1 established the parameters of the paradigm in non-patient participants, and Experiment 2 contrasted OCD checkers with OCD washers and non-patients.Results for both subjective and physiological measures of security motivation closely replicated previous findings for washing behavior. Groups did not differ significantly in initial activation, but the OCD checkers were unable to reduce their activation by engaging in period of checking that was ample for returning controls to baseline.The sample size for the patient groups was modest.These results lend further support to the security-motivation theory of OCD.

Somatosensory amplification and its relationship to heartbeat detection ability.

Somatosensory amplification has been defined as the tendency to experience normal bodily sensations as intense, noxious, and disturbing. The present experiment investigated whether this tendency is due to heightened physiological sensitivity to bodily sensations. The relationship between Somatosensory Amplification Scale (SSAS) scores and objective measures of the ability to detect bodily (ie, heartbeat) sensations derived from the Method of Constant Stimuli procedure was assessed. Although somatosensory amplification characterizes hypochondriacs, the relationship between somatosensory amplification and sensitivity to bodily sensations was examined in nonhypochondriacal, nonpatient participants in an effort to dissociate somatosensory amplification from other variables associated with hypochondriasis and/or patient status. Heartbeat detectors were found to exhibit significantly lower SSAS scores than nondetectors. This finding suggests that somatosensory amplification is not due to heightened sensitivity to bodily sensations.

Self-discrepancies and causal attributions: studies of hypothesized relationships.

The self-concept and causal attributions are both centrally implicated in psychological disorders including depression and paranoia. In two investigations of the dynamic relationships between causal attributions and self-representations, non-patient participants completed questionnaires derived from Higgins' (1987) Self-Discrepancy Theory before and after completing a measure of causal attribution. In Study 1, consistent with cognitive models of depression, external attributions for negative events were associated with reductions in self-actual:self-ideal discrepancies. Study 2 revealed significantly different effects on self-discrepancies of three types of causal attributions. Internal attributions led to increased self-actual:self-ideal discrepancies as well as increased discrepancies between self-perceptions and the believed views of others about the self (self-actual:other-actual discrepancies). External situational attributions led to no changes in either self-actual:self-ideal or self-actual:other-actual discrepancies. External personal attributions led to no changes in self-actual:self-ideal discrepancies but increased self-actual:other-actual discrepancies. These findings point to the value of distinguishing between different kinds of external attributions. They show that self-representations and causal attributions are closely coupled cognitive domains. The results also suggest that paranoid ideation might be specifically associated with external-personal attributions for negative events.

PREDICTORS OF ANALOGUE POST-TRAUMATIC INTRUSIVE COGNITIONS

Previous research on vulnerability to Post-Traumatic Stress Disorder (PTSD) has been restricted by the absence of prospective studies that measure individual differences prior to traumatization. This study investigated the predictors of analogue post-traumatic intrusive cognitions using a fully prospective design. Non-patient participants completed a range of predictor measures before being exposed to a film about a traumatic fire. Film-induced changes in negative mood were also assessed. Subsequent intrusions were measured both within the experimental session and for a further seven days. The hypothesized predictors were: neuroticism, trait anxiety, extraversion, depression, a general tendency to suppress unpleasant thoughts, beliefs about being “at risk” from fire, mental imagery, self-rated proneness to intrusions and negative mood changes. The results showed that intrusions were predicted by film-induced increases in negative mood, thought suppression tendencies, beliefs about vulnerability to fire and self-rated proneness to intrusive cognitions. The findings are discussed in relation to the literature on thought suppression and cognitive processes in PTSD.