Dean McKay

Psychometric validation of the Obsessive Beliefs Questionnaire and the Interpretation of Intrusions Inventory: Part I

This article reports on the validation of the Obsessive Beliefs Questionnaire (OBQ) and Interpretations of Intrusions Inventory (III) developed by the Obsessive Compulsive Cognitions Working Group (OCCWG) to assess the primary beliefs and appraisals considered critical to the pathogenesis of obsessions. A battery of questionnaires that assessed symptoms of anxiety, depression, obsessive-compulsive symptoms and worry was administered to 248 outpatients with a DSM-IV diagnosis of Obsessive-Compulsive Disorder (OCD), 105 non-obsessional anxious patients, 87 non-clinical adults from the community, and 291 undergraduate students. Tests of internal consistency and test-retest reliability indicated that the OBQ and III assessed stable aspects of OC-related thinking. Between-group differences and correlations with existing measures of OC symptoms indicated that the OBQ and III assess core cognitive features of obsessionality. However, the various subscales of the OBQ and III are highly correlated, and both measures evidenced low discriminant validity. The findings are discussed in terms of the relevance and specificity of cognitive constructs like responsibility, control and importance of thoughts, overestimated threat, tolerance of uncertainty and perfectionism for OCD.

Neuropsychology of Obsessive-Compulsive Disorder: A Review and Treatment Implications

The existing literature examining neuropsychological features of obsessive-compulsive disorder (OCD) is reviewed. The accumulated research points to a deficit in organizational strategies in general, suggesting problems in executive functioning. The available research is inconsistent in identifying memory deficits in OCD. However, memory problems are most evident when tests are used that require an implicit organizational strategy. While the majority of the research reviewed involves adult samples, there is emerging evidence that these deficits are present in children as well. It is suggested here that the interaction between organizational strategy deficits and the effort to recall unstructured information contributes to doubting, an important feature of OCD. Implications of this body of research for behavior therapy are considered.

The relevance of analogue studies for understanding obsessions and compulsions

Analogue samples are often used to study obsessive-compulsive (OC) symptoms and related phenomena. This approach is based on the hypothesis that results derived from such samples are relevant to understanding OC symptoms in individuals with a diagnosis of obsessive-compulsive disorder (OCD). Two decades ago, Gibbs (1996) reviewed the available literature and found initial support for this hypothesis. Since then there have been many important advances addressing this issue. The purpose of the present review was to synthesize various lines of research examining the assumptions of using analogue samples to draw inferences about people with OCD. We reviewed research on the prevalence of OC symptoms in non-clinical populations, the dimensional (vs. categorical) nature of these symptoms, phenomenology, etiology, and studies on developmental and maintenance factors in clinical and analogue samples. We also considered the relevance of analogue samples in OCD treatment research. The available evidence suggests research with analogue samples is highly relevant for understanding OC symptoms. Guidelines for the appropriate use of analogue designs and samples are suggested.

The overvalued ideas scale: development, reliability and validity in obsessive–compulsive disorder

The presence of overvalued ideas in obsessive-compulsive disorder (OCD) has been theoretically linked to poorer treatment outcome [Kozak, M. J. & Foa, E. B. (1994). Obsessions, overvalued ideas and delusions in obsessive-compulsive disorder. Behaviour Research and Therapy, 32, 343-353]. To date, no measures have been developed which quantitatively assess levels of overvalued ideas in obsessive-compulsives. The present studies examined the psychometric properties of a scale developed to measure this form of psychopathology, the Overvalued Ideas Scale (OVIS). In study 1, 102 patients diagnosed with OCD were administered a battery of instruments including the OVIS at baseline and two weeks later, prior to initiating treatment. Results indicate that the OVIS has adequate internal consistency reliability (coefficient alpha = 0.88 at baseline), test-retest reliability (r = 0.86) and interrater reliability (r = 0.88). Moderate to high levels of convergent validity was found with measures of obsessive-compulsive symptoms, a single item assessment of overvalued ideas and psychotic symptoms. Medium levels of discriminant validity with measures of anxiety and depression was obtained in this study. Individuals determined to have high OVI showed greater stability of this pathology than those with lower OVI, suggesting that overvalued ideas are stable for extreme scorers. In study 2 a total of 40 patients participated who were diagnosed with OCD. The same battery of instruments was administered as in study 1, as well as the Beck Depression Inventory and Beck Anxiety Inventories. Results were similar to that obtained in study 1, including a relative lack of discriminant validity with self-report measures of depression and anxiety. It is suggested that further research with the OVIS may show predictive value in treatment outcome studies of OCD.

Is disgust associated with psychopathology? Emerging research in the anxiety disorders

Recent evidence indicates that the propensity towards experiencing disgust may contribute to the development and maintenance of some anxiety disorders. This article summarizes the empirical evidence with emphasis on illuminating potential mediators, moderators, and mechanisms of the disgust-anxiety disorder association that may inform the development of an integrative conceptual model. Early research using neuroimaging methods suggest that disgust processing is associated with activation of the insula. This research has the potential to facilitate progress in developing an empirically informed psychobiological theory on the causal role of disgust in the anxiety disorders.

Multiple pathways to functional impairment in obsessive-compulsive disorder

Obsessive-compulsive disorder (OCD) is a chronic and debilitating condition that is relatively common in both children and adults, and it is associated with a wide range of functional impairments. Mental health researchers and practitioners have placed considerable attention on OCD over the past two decades, with the goal of advancing treatment and understanding its etiology. Until recently, it was unknown to what extent this disorder was associated with functional impairment. However, recent research shows that the condition has significant social and occupational liabilities. This article discusses etiology, common symptom presentations (including comorbid and ancillary symptoms), basic OCD subtypes, neuropsychological functioning, and the relation these have with functional disability in OCD. Recommendations for future research are also considered.

Attention bias for disgust.

Disgust was originally theorized as a defense against the oral incorporation of offensive objects. Recent research suggests disgust serves as a defense against a wider range of objects and situations in the environment, and may contribute to phobic avoidance. As such, disgust sensitivity was explored for attention and memory biases. Using a sample of 60 undergraduates, an attention bias towards disgust words on a Stroop Color-naming Task was found across all subjects following an emotional priming task. When participants were primed with disgust stories, disgust sensitivity was positively related to latencies on disgust words on a Stroop Color-naming Task, while unrelated in the other groups (fear or neutral primed). Similarly, those same participants demonstrated a positive correlation between their disgust sensitivity and the number of disgust words recalled following the Stroop Task. This, along with the findings of relationships between disgust sensitivity and contamination fears related to obsessive-compulsiveness and eating related symptomatology call for further empirical investigation into the role that disgust plays in psychopathology.

Non-adherence and non-response in the treatment of anxiety disorders

Among the best established treatments for anxiety disorders are cognitive-behavioral interventions and serotonin reuptake inhibitors. Although clinically useful, these therapies are far from universally efficacious; some patients are unable to complete treatment, and many treatment completers fail to achieve clinically significant improvement. A review of meta-analyses on the treatment of anxiety disorders reveals that about a fifth of patients drop out prematurely and a third of treatment completers are classified as non-responders. In this article we examine the predictors of, and potential solutions for, the problems of treatment non-adherence and non-response to cognitive-behavioral and serotonergic treatments of adult anxiety disorders. Despite decades of research, few reliable predictors have been identified, and no predictor has been consistently supported in the literature. However, there is suggestive evidence that risk of premature dropout is associated with low treatment motivation, side effects, and practical barriers to attending sessions. There is also suggestive evidence that poor response is associated with severe pretreatment psychopathology and comorbidity, as well as high expressed emotion in the patients family environment. Methods for better estimating treatment prognosis are proposed and possible directions for improving treatment outcome are discussed.

Predictive validity of the overvalued ideas scale: outcome in obsessive-compulsive and body dysmorphic disorders.

Overvalued ideas have been theoretically implicated in treatment failure for obsessive-compulsive disorder (OCD). Until recently, there have not been valid assessments for determining severity of overvalued ideas. One recent scale, the Overvalued Ideas Scale (OVIS; Neziroglu, McKay, Yaryura-Tobias, Stevens & Todaro, 1999, Behaviour Research and Therapy, 37, 881-902) has been found to validly measure overvalued ideas. However, its predictive utility has not been determined. Two studies were conducted to examine the extent to which the OVIS predicts treatment response. Study 1 examined the response to behavioral therapy in a group of participants diagnosed with OCD. Residual gain scores showed a significant correlation between treatment outcome for compulsions and pretreatment OVIS scores (28.1% variance accounted). Pretreatment OVIS scores were not significantly correlated with residual gains in obsessions (1.7% variance accounted). The predictive utility of the OVIS was superior to a single item assessment of overvalued ideas available on the Yale-Brown Obsessive Scale in predicting outcome for compulsions. For this item, the variance accounted for compulsions was 6.3% and for obsessions was 3.9%. Study 2 examined the response to behavioral therapy in a group of participants diagnosed with body dysmorphic disorder (BDD), a condition ostensibly linked to OCD and presumed to present with higher levels of overvalued ideas. Residual gains scores showed a significant relationship between obsessions and OVIS (accounting for 34.8% of the variance), but not for compulsions (10.2% variance accounted). As in Study 1, the predictive utility of the OVIS was superior to the single item assessment (with 0.2% variance accounted for compulsions, 2.4% variance accounted for obsessions). Taken together, the studies reported here show that this OVIS is predictive of treatment outcome, and the predictive value depends on which symptoms are used to assess outcome. Further, the scale is more effective in predicting outcome than a widely used single item assessment.

Factor structure of the Yale-Brown Obsessive-Compulsive scale: A two dimensional measure

The Yale-Brown Obsessive-Compulsive Scale (Y-BOCS: Goodman, Price, Rasmussen, Mazure, Fleischman, Hill, Heninger & Charney, 1989a, b, Archives of General Psychiatry, 46, 1006-1016), a widely used measure of obsessions and compulsions, is typically used by summing the items to yield a global measure of symptom severity. However obsessive-compulsive disorder (OCD) is characterized by two distinct groups of symptoms (i.e. obsessions and compulsions), and so it was hypothesized that OCD, as assessed by the Y-BOCS, may be two dimensional. In other words, the items assessing obsessions may be factorially distinct from the items assessing compulsions. A confirmatory factor analysis (CFA) was conducted using responses from 83 OCD patients to determine whether OCD as assessed with the Y-BOCS is unidimensional or forms two distinct dimensions. Results supported a two-factor solution, and suggest that items assessing obsessions should be scored as one subscale, and items assessing compulsions scored as a separate subscale. Depression, as assessed by the Beck Depression Inventory, (Beck, Ward, Mendelsohn, Mock & Erbaugh, 1961, Archives of General Psychiatry, 4, 561-571), was correlated with both subscales. Trait anxiety, as assessed by the State-Trait Anxiety Inventory (Speilberger, 1983, Manual for the State-Trait Anxiety Inventory (Form Y). Palo-Alto, CA: Consulting Psychologists Press), was correlated with the obsessions subscale but not with the compulsions subscale.