Taxometric and factor analytic models of anxiety sensitivity among youth: exploring the latent structure of anxiety psychopathology vulnerability

Dimensions over categories: a meta-analysis of taxometric research

Taxometric procedures have been used extensively to investigate whether individual differences in personality and psychopathology are latently dimensional or categorical ('taxonic'). We report the first meta-analysis of taxometric research, examining 317 findings drawn from 183 articles that employed an index of the comparative fit of observed data to dimensional and taxonic data simulations. Findings supporting dimensional models outnumbered those supporting taxonic models five to one. There were systematic differences among 17 construct domains in support for the two models, but psychopathology was no more likely to generate taxonic findings than normal variation (i.e. individual differences in personality, response styles, gender, and sexuality). No content domain showed aggregate support for the taxonic model. Six variables - alcohol use disorder, intermittent explosive disorder, problem gambling, autism, suicide risk, and pedophilia - emerged as the most plausible taxon candidates based on a preponderance of independently replicated findings. We also compared the 317 meta-analyzed findings to 185 additional taxometric findings from 96 articles that did not employ the comparative fit index. Studies that used the index were 4.88 times more likely to generate dimensional findings than those that did not after controlling for construct domain, implying that many taxonic findings obtained before the popularization of simulation-based techniques are spurious. The meta-analytic findings support the conclusion that the great majority of psychological differences between people are latently continuous, and that psychopathology is no exception.

Investigating the latent structure of distress intolerance

Distress intolerance (DI) is defined as a perceived or actual inability to withstand distressing emotional or somatic states, which motivates the use of avoidance strategies. Despite widespread interest in DI, key questions about its underlying structure remain unanswered. The current study evaluated the latent structure of DI in two large samples using four-indicators and three taxometric procedures (MAMBAC, MAXEIG, and L-Mode). Data interpretation relied primarily on the Comparison Curve Fit Indices (CCFI). Overall, results from the three non-redundant procedures suggested that DI was more accurately characterized by a dimensional rather than a categorical conceptualization. Implications for assessment and conceptual models of DI are discussed.

Fear of the unknown: One fear to rule them all?

The current review and synthesis was designed to provocatively develop and evaluate the proposition that "fear of the unknown may be a, or possibly the, fundamental fear" (Carleton, 2016) underlying anxiety and therein neuroticism. Identifying fundamental transdiagnostic elements is a priority for clinical theory and practice. Historical criteria for identifying fundamental components of anxiety are described and revised criteria are offered. The revised criteria are based on logical rhetorical arguments using a constituent reductionist postpositivist approach supported by the available empirical data. The revised criteria are then used to assess several fears posited as fundamental, including fear of the unknown. The review and synthesis concludes with brief recommendations for future theoretical discourse as well as clinical and non-clinical research.

Examining the latent structure of anxiety sensitivity in adolescents using factor mixture modeling

Anxiety sensitivity has been implicated as an important risk factor, generalizable to most anxiety disorders. In adults, factor mixture modeling has been used to demonstrate that anxiety sensitivity is best conceptualized as categorical between individuals. That is, whereas most adults appear to possess normative levels of anxiety sensitivity, a small subset of the population appears to possess abnormally high levels of anxiety sensitivity. Further, those in the high anxiety sensitivity group are at increased risk of having high levels of anxiety and of having an anxiety disorder. This study was designed to determine whether these findings extend to adolescents. Factor mixture modeling was used to examine the best fitting model of anxiety sensitivity in a sample of 277 adolescents (M age = 11.0 years, SD = 0.81). Consistent with research in adults, the best fitting model consisted of 2 classes, 1 containing adolescents with high levels of anxiety sensitivity (n = 25) and another containing adolescents with normative levels of anxiety sensitivity (n = 252). Examination of anxiety sensitivity subscales revealed that the social concerns subscale was not important for classification of individuals. Convergent and discriminant validity of anxiety sensitivity classes were found in that membership in the high anxiety sensitivity class was associated with higher mean levels of anxiety symptoms, controlling for depression and externalizing problems, and was not associated with higher mean levels of depression or externalizing symptoms controlling for anxiety problems.

Factor mixture model of anxiety sensitivity and anxiety psychopathology vulnerability

BACKGROUND

The purpose of the present study was to shed light on the latent structure and nature of individual differences in anxiety sensitivity (AS) and related risk for psychopathology.

METHODS

The present study evaluated the latent structure of AS using factor mixture modeling (FMM; Lubke and Muthén, 2005) and tested the relations between the observed FMM-based model of AS and psychopathology in a large, diverse adult clinical research sample (N=481; 57.6% women; M(SD)(age)=36.6(15.0) years).

RESULTS

Findings showed that a two-class three-factor partially invariant model of AS demonstrated significantly better fit than a one-class dimensional model and more complex multi-class models. As predicted, risk conferred by AS taxonicity was specific to anxiety psychopathology, and not to other forms of psychopathology.

LIMITATIONS

The sample was not epidemiologic, self-report and psychiatric interview data were used to index AS and psychopathology, and a cross-sectional design limited inference regarding the directionality of observed relations between AS and anxiety psychopathology.

CONCLUSIONS

Findings are discussed with respect to the nature of AS and related anxiety psychopathology vulnerability specifically, as well as the implications of factor mixture modeling for advancing taxonomy of vulnerability and psychopathology more broadly.

Exploration of a factor mixture-based taxonic-dimensional model of anxiety sensitivity and transdiagnostic psychopathology vulnerability among trauma-exposed adults

The aim of this study was to evaluate the associations between a factor mixture-based taxonic-dimensional model of anxiety sensitivity (AS) and posttraumatic stress, panic, generalized anxiety, depression, psychiatric multimorbidity, and quality of life among a young adult sample exposed to traumatic stress (N = 103, n (females) = 66, M (age) = 23.68 years, SD (age) = 9.55). Findings showed support for the conceptual and operational utility of the AS taxonic-dimensional model with respect to concurrent transdiagnostic vulnerability among trauma-exposed adults. Specifically, relative to the low-AS group, the high-AS group demonstrated elevated levels of panic, depressive, and posttraumatic stress symptom severity as well as greater psychiatric multimorbidity and poorer quality of life. Furthermore, past-month MDD, GAD, PTSD, and panic attacks occurred nearly exclusively among the high-AS group. Continuous AS physical and psychological concerns scores were found to be significantly related to levels of panic and posttraumatic stress symptom severity, psychiatric multimorbidity as well as panic attack status only among the high-AS group and not among the low-AS group. Findings are discussed with respect to their implications for the conceptual and operational utility of the FMM-based taxonic-dimensional model of AS, related vulnerability for psychopathology in the context of trauma, and the clinical implications of these findings for assessment and intervention.

Nature and role of change in anxiety sensitivity during NRT-aided cognitive-behavioral smoking cessation treatment

This study evaluated the associations between change in anxiety sensitivity (AS; fear of the negative consequences of anxiety and related sensations) and lapse and relapse during a 4-week group NRT-aided cognitive-behavioral Tobacco Intervention Program. Participants were 67 (44 women; M (age) = 46.2 years, SD = 10.4) adult daily smokers. Results indicated that participants who maintained high levels of AS from pretreatment to 1 month posttreatment, compared to those who demonstrated a significant reduction in AS levels during this time period, showed a significantly increased risk for lapse and relapse. Further inspection indicated that higher continuous levels of AS physical and psychological concerns, specifically among those participants who maintained elevated levels of AS from pre- to posttreatment, predicted significantly greater risk for relapse. Findings are discussed with respect to better understanding change in AS, grounded in an emergent taxonic-dimensional factor mixture model of the construct, with respect to lapse and relapse during smoking cessation.

Categories versus dimensions in personality and psychopathology: a quantitative review of taxometric research

Taxometric research methods were developed by Paul Meehl and colleagues to distinguish between categorical and dimensional models of latent variables. We have conducted a comprehensive review of published taxometric research that included 177 articles, 311 distinct findings and a combined sample of 533 377 participants. Multilevel logistic regression analyses have examined the methodological and substantive variables associated with taxonic (categorical) findings. Although 38.9% of findings were taxonic, these findings were much less frequent in more recent and methodologically stronger studies, and in those reporting comparative fit indices based on simulated comparison data. When these and other possible confounds were statistically controlled, the true prevalence of taxonic findings was estimated at 14%. The domains of normal personality, mood disorders, anxiety disorders, eating disorders, externalizing disorders, and personality disorders (PDs) other than schizotypal yielded little persuasive evidence of taxa. Promising but still not definitive evidence of psychological taxa was confined to the domains of schizotypy, substance use disorders and autism. This review indicates that most latent variables of interest to psychiatrists and personality and clinical psychologists are dimensional, and that many influential taxonic findings of early taxometric research are likely to be spurious.

Annual research review: categories versus dimensions in the classification and conceptualisation of child and adolescent mental disorders--implications of recent empirical study

The question of whether child and adolescent mental disorders are best classified using dimensional or categorical approaches is a contentious one that has equally profound implications for clinical practice and scientific enquiry. Here, we explore this issue in the context of the forth coming publication of the DSM-5 and ICD-11 approaches to classification and diagnosis and in the light of recent empirical studies. First, we provide an overview of current category-based systems and dimensional alternatives. Second, we distinguish the various strands of meaning and levels of analysis implied when we talk about categories and dimensions of mental disorder--distinguishing practical clinical necessity, formal diagnostic systems, meta-theoretical beliefs and empirical reality. Third, we introduce the different statistical techniques developed to identify disorder dimensions and categories in childhood populations and to test between categorical and dimensional models. Fourth, we summarise the empirical evidence from recent taxometric studies in favour of the 'taxonomic hypothesis' that mental disorder categories reflect discrete entities with putative specific causes. Finally, we explore the implications of these findings for clinical practice and science.

Factor Structure and Psychometric Properties of the Anxiety Sensitivity Index in a Sample of Croatian Adults

Anxiety sensitivity (AS) refers to a person’s tendency to fear anxiety-related symptoms due to the belief that these symptoms may have harmful consequences. The most widely used operationalization of AS in adults is the Anxiety Sensitivity Index (ASI). The factor structure, gender stability, and psychometric properties of the ASI in a sample of Croatian adults ( N = 984) were evaluated. Results confirm the multidimensional and hierarchical structure of the ASI, which consisted of three lower-order factors (Physical Concerns, Psychological Concerns, and Social Concerns) and a single higher-order factor, AS. Furthermore, the achievement of normative scores for the ASI in a Croatian adult sample demonstrates the cross-national stability of the ASI. Reliability coefficients for the ASI, Physical Concerns, and Psychological Concerns are high and satisfactory in the total sample and for both genders. Overall, the results confirmed the cross-national stability, gender stability, reliability, and validity of the ASI in a sample of Croatian adults.

Revisiting the latent structure of the anxiety sensitivity construct: more evidence of dimensionality

Anxiety sensitivity (AS) was initially conceptualized as existing along a continuum; however, emerging evidence from taxometric analyses is mixed as to whether the latent structure of AS is dimensional or taxonic. The purpose of the present study was to further evaluate the latent structure of AS in an effort to clarify the contrasting findings reported in the literature. To do so, we examined the latent structure of AS in two large independent samples unselected with regard to AS level (comprising undergraduate respondents and/or community residents). MAXEIG and MAMBAC analyses were performed with indicator sets drawn from distinct self-report measures of AS within either sample. MAXEIG and MAMBAC, as well as comparison analyses utilizing simulated taxonic and dimensional datasets, yielded converging evidence that AS has a dimensional latent structure. Implications of these finding for the conceptualization and measurement of AS are discussed and future research directions are highlighted.

Anxiety as a context for understanding associations between hypochondriasis, obsessive-compulsive, and panic attack symptoms

In the context of the integrative model of anxiety and depression, we examined whether the essential problem of hypochondriasis is one of anxiety. When analyzed, data from a large nonclinical sample corresponded to the integrative model's characterization of anxiety as composed of both broad, shared and specific, unique symptom factors. The unique hypochondriasis, obsessive-compulsive, and panic attack symptom factors all had correlational patterns expected of anxiety with the shared, broad factors of negative emotionality and positive emotionality. A confirmatory factor analysis showed a higher-order, bifactor model was the best fit to our data; the shared and the unique hypochondriasis and anxiety symptom factors both contributed substantial variance. This study provides refinements to an empirically based taxonomy and clarifies what hypochondriasis is and, importantly, what it is not.

Dimensional, categorical, or dimensional-categories: testing the latent structure of anxiety sensitivity among adults using factor-mixture modeling

The present study tested multiple, competing latent structural models of anxiety sensitivity (AS), as measured by the Anxiety Sensitivity Index-3 (ASI-3; Taylor et al., 2007). Data were collected from 3 sites in North America (N=634). Participants were predominantly university students (M=21.3 years, SD=5.4). ASI-3 data were evaluated using an integration of mixture modeling and confirmatory factor analysis-factor mixture modeling (FMM; Muthén, 2008). Results supported a 2-class 3-factor partially invariant model of AS. Specifically, the FMM analyses indicated that AS is a taxonic (two-class) variable, and that each categorical class has a unique multidimensional factor structure. Consistent with the specific point-prediction regarding the hypothesized parameters of the putative latent class variable, FMM indicated that the putatively "high-risk" subgroup of cases or latent form of AS composed approximately 12% of the studied sample whereas the putatively "normative" subgroup of cases or latent form of AS composed 88% of the sample. In addition, the AS Physical and Psychological Concerns subscales, but not the Social Concerns subscale, most strongly discriminated between the two latent classes. Finally, comparison of continuous levels of AS Physical and Psychological Concerns between FMM-derived AS latent classes and independent clinical samples of patients with anxiety disorders provided empirical support for the theorized taxonic-dimensional model of AS and anxiety psychopathology vulnerability. Findings are discussed in regard to the implications of this and related research into the nature of AS and anxiety psychopathology vulnerability.

Categorical or dimensional: a reanalysis of the anxiety sensitivity construct

Anxiety sensitivity, or the fear of anxiety sensations, has been implicated in the etiology of anxiety disorders, particularly panic disorder. Recently, inconsistent findings have been reported regarding the latent structure of anxiety sensitivity. Whereas some taxometric studies of anxiety sensitivity have reported evidence of categorical latent structure, others have found evidence of a latent dimension. The purpose of the present research was to further examine the latent structure of anxiety sensitivity using taxometric procedures and commonly utilized measures of anxiety sensitivity. To this end, three mathematically independent taxometric procedures (MAXEIG, MAMBAC, and L-Mode) were applied to data collected from two large nonclinical samples (n's=1,171 and 2,173) that completed the Anxiety Sensitivity Index and the Anxiety Sensitivity Index-Revised. Results from both studies converged in support of a dimensional conceptualization of anxiety sensitivity. A third study was conducted using indicators derived from the newly revised Anxiety Sensitivity Index-3 in a separate sample of 1,462 nonclinical participants. Results of these analyses provided further support for a dimensional anxiety sensitivity solution. The implications of these results for anxiety sensitivity research are discussed, and several potential directions for future research are considered.

The relationship between anxiety sensitivity and latent symptoms of emotional problems: A structural equation modeling approach

A large body of research suggests that common and specific psychopathology dimensions underlie the symptoms that occur within mood and anxiety disorders. As of yet, it is unclear precisely how the facets of Anxiety Sensitivity (AS), or fear of the symptoms of fear and anxiety, relate to these latent factors. Using data from 606 adolescents participating in the baseline phase of a longitudinal study on risk factors for emotional disorders, we modeled the facets of AS as measured by the Anxiety Sensitivity Index-Expanded Form (ASI-X) and related these facets to a hierarchical model of latent symptoms of psychological distress. Results suggest that one facet of AS is associated with a broad General Distress factor underlying symptoms of most emotional disorders while others relate to intermediate-level and conceptually-meaningful narrow factors representing aspects of psychological distress specific to particular emotional disorders.

Temporal and structural dynamics of anxiety sensitivity in predicting fearful responding to a 35% CO2 challenge

The current study assessed the incremental prediction of anxiety sensitivity (AS) in both taxonic (categorical) and dimensional representations at various time points before and after a single vital capacity inhalation of a 35% CO(2), 65% balanced O(2) gas mixture. Participants were 128 young adults screened for a history of panic attacks. By controlling for traitwise factors including state anxiety and testing both categorical and continuous conceptualizations of the AS construct at various timepoints, the present report was able to evaluate the temporal and structural dynamics of AS in relation to fearful responding to the challenge. Relevant variables were evaluated in a hierarchical linear regression framework, and it was found that a continuous conceptualization of AS provided incremental predictive validity above and beyond trait anxiety immediately post-challenge, while a categorical representation of AS was equivalent to a continuous model of AS at post-challenge but outperformed a continuous model at follow-up. These data provide basic but important evidence suggesting that AS is uniquely associated with anxious responding to a 35% CO(2) challenge, and that categorical representations of AS should be considered in biological challenge studies.

The facets of anxiety sensitivity in adolescents

This study examined the factor structure, reliability, and validity of the German translation of the Childhood Anxiety Sensitivity Index (CASI). A total of 1292 adolescents participated in the study. Analyses using the Schmid-Leiman solution showed the CASI to have one higher order factor and three orthogonal lower order factors. CASI scores correlated significantly with anxiety symptoms and with general difficulties. Hierarchical multiple regression showed CASI to make a significant contribution in predicting anxiety even after controlling for variance due to general difficulties, thus giving further support to the incremental validity of the CASI. The CASI is a potentially useful measure to include in longitudinal studies that examine the development of childhood and adolescent anxiety disorders.

Laboratory test of a novel structural model of anxiety sensitivity and panic vulnerability

The current study evaluated a novel latent structural model of anxiety sensitivity (AS) in relation to panic vulnerability among a sample of young adults (N=216). AS was measured using the 16-item Anxiety Sensitivity Index (ASI; Reiss, Peterson, Gursky, & McNally, 1986), and panic vulnerability was indexed by panic attack responding to a single administration of a 4-minute, 10% CO(2) challenge. As predicted, vulnerability for panic attack responding to biological challenge was associated with dichotomous individual differences between taxonic AS classes and continuous within-taxon class individual differences in AS physical concerns. Findings supported the AS taxonic-dimensional hypothesis of AS latent structure and panic vulnerability. These findings are discussed in terms of their theoretical and clinical implications.

Evaluation of anxiety sensitivity among daily adult smokers using item response theory analysis

The present investigation applied Item Response Theory (IRT) methodology to the 16-item Anxiety Sensitivity Index (ASI) [Reiss, S., Peterson, R. A., Gursky, M., & McNally, R. J. (1986). Anxiety sensitivity, anxiety frequency, and the prediction of fearfulness. Behaviour Research and Therapy, 24, 1-8] for a sample of 475 daily adult smokers (52% women; M(age)=26.9, S.D.=11.1, range=18-65). Using non-parametric item response analysis, all 16 ASI items were evaluated. Evaluation of the option characteristic curves for each item revealed 4 poorly discriminating ASI items (1: "It is important not to appear nervous;" 5: "It is important to me to stay in control of my emotions;" 7: "It embarrasses me when my stomach growls;" 9: "When I notice my heart beating rapidly, I worry that I might be having a heart attack"), which were dropped from analysis. Upon repeat analysis, the remaining items appeared to make adequate separations within levels of anxiety sensitivity in this sample. Graded response modeling data indicated important differences in ASI items' capacity to discriminate between, and provide information about, latent levels of anxiety sensitivity. Specifically, three items best discriminated and provided the most information regarding latent levels of AS-items 3, 15, and 16. Items 1, 5, 7, and 9 were omitted due to their limited capacity to discriminate between latent levels of anxiety sensitivity; items 8, 12, and 13 also performed poorly. Overall, current findings suggest that evaluation of anxiety sensitivity among adult smokers using the 16-item ASI may usefully choose to focus on items that performed well in these IRT analyses (items: 2, 3, 4, 6, 10, 11, 14, 15, and 16).

The efficacy of cognitive-behavioral interventions for reducing anxiety sensitivity: a meta-analytic review

The present study meta-analytically reviewed the efficacy of cognitive-behavioral therapy (CBT) vs. control conditions in the reduction of anxiety sensitivity. A computerized search was conducted to identify CBT outcome studies that included the Anxiety Sensitivity Index as a dependent variable. Of the 989 studies that were identified, 24 randomized-controlled trials with a total of 1851 participants met inclusion criteria and were included in the analysis. Data were extracted separately for treatment-seeking (16 studies) and at-risk (eight studies) samples. Results indicated large effect sizes for treatment-seeking samples, Hedges' g=1.40, SE=0.21, 95% CI: 1.00-1.81, p<0.001, and moderate to large effect sizes for at risk samples Hedges' g=0.74, SE=0.18, 95% CI: 0.39-1.08, p<0.001. Additionally, both the amount of therapist contact and control modality (waitlist vs. psychological control) moderated the effect sizes for treatment-seeking samples. Our review indicates that CBT is efficacious in reducing anxiety sensitivity. However, more research is needed to determine the mechanisms by which CBT exert its effects on anxiety sensitivity.