Confirmatory and exploratory factor analysis of the distress tolerance scale (DTS) in a clinical sample of eating disorder patients

Abstract

A confirmatory factor analysis of the factor structure of the Distress Tolerance Scale (DTS) created by Corstorphine et al. [Corstorphine, E., Mountford, V., Tomlinson, S., Waller, G., & Meyer, C. (2007). Distress tolerance in the eating disorders. Eating Behaviors, 8, 91–97.] was conducted to assess whether the scale's purported three factors emerged in a clinical sample of patients with a DSM-IV diagnosed eating disorder. The original three-factor model was generally considered to be a poor fit for the data. Subsequent exploratory factor analysis indicated that a better fit emerged using a four-factor structure. Significant associations were observed between behavioral avoidance of positive affect and eating disorder psychopathology. Implications for use of the DTS with eating disorder patients are discussed.

Introduction

Distress tolerance is defined as the ability to endure and accept intense affect so that problem solving can take place (Linehan, 1993). Individuals with low distress tolerance are likely to find intense emotional experiences unbearable and will therefore act quickly to alleviate these emotional experiences (Simons & Gaher, 2005). Indeed, empirical studies support a relationship between poor distress tolerance and engagement in maladaptive mood-modulatory behaviors such as smoking and other substance misuse (e.g., Brown et al., 2002, Daughters et al., 2005). Avoidance of affect is a particularly important feature of poor distress tolerance and it has been proposed that avoidance of affect contributes to a range of psychological problems, including avoidant personality disorder, social anxiety disorder, health anxiety and eating disorders (Butler & Surawy, 2004).

In the past decade there has been increasing interest in the role of distress tolerance and its contribution to eating disorder psychopathology. Models of the maintenance of eating disorders purport that the ability to tolerate intense affect is diminished in patients with eating disorders (e.g., Cooper et al., 2004, Fairburn et al., 2003). Moreover, there is clinical and empirical evidence that affective states often precipitate disordered eating behaviors. This is particularly evident in relation to binge eating, which is thought to perform a functional role by comforting and distracting one's self from distressing emotions (e.g., Agras and Telch, 1998, Fahy and Eisler, 1993, McManus and Waller, 1995). Anorexia nervosa (AN) and restrictive behaviors have been associated with alexithymia, a cognitive-attention deficit that involves difficulties in processing, regulating, and communicating affect (Schmidt, Jiwany, & Treasure, 1993) and this association has been found to be independent of comorbid affective disorders (Bydlowski et al., 2005). Despite evidence of an association between affective states and disordered eating behaviors, there is limited empirical evidence that distress tolerance mediates this relationship. This is primarily because measures of distress tolerance for use with eating disorder patients have not been available.

Two different self-report measures of distress tolerance (each of which has been named the Distress Tolerance Scale) have recently been developed (Corstorphine et al., 2007, Simons and Gaher, 2005). Although both measures were designed to assess the construct of distress tolerance, there are notable differences between these measures. The distress tolerance scale developed by Simons and Gaher (2005) comprises 15 questions pertaining to processes that make up the global construct of distress tolerance, such as perceived ability to tolerate emotional states (e.g., “feeling distressed or upset is unbearable to me”), extent to which attention is absorbed by distressing emotions (e.g., “my feelings of distress are so intense that they completely take over”), subjective appraisal of emotions (e.g., “my feelings of distress or being upset are not acceptable”), and regulation efforts to mitigate distress (e.g., “I'll do anything to stop feeling distressed”). Participants rate responses on a 5-point Likert scale ranging from 1 (“strongly agree”) to 5 (“strongly disagree”). The scale yields a Global score of distress tolerance and four subscale scores (Tolerance, Appraisal, Absorption, and Regulation). Lower scores indicate poorer tolerance for distressing emotions. The measure was validated with a large sample of university students (Simons & Gaher, 2005) and a recent cross-sectional study found that poor distress tolerance predicted elevated bulimic symptomatology (measured by the Eating Disorder Inventory — Bulimia subscale) in a sample of non-eating-disordered university students, even after controlling for potential covariates such as depressive and anxiety symptoms, impulsivity, and perfectionism (Anestis, Selby, Fink, & Joiner, 2007). This measure of distress tolerance has not been validated with a clinical sample of eating disorder patients.

Corstorphine et al. (2007) developed the Distress Tolerance Scale (DTS) and validated the instrument in a mixed sample comprising 72 treatment-seeking women with a diagnosed eating disorder who were recruited from a specialist community-based eating disorders service in Britain and 62 non-clinical control women recruited from undergraduate and graduate populations at a British university. The clinical group comprised 19 patients who met diagnostic criteria for AN, 25 who met criteria for bulimia nervosa (BN), and 28 who met criteria for eating disorder not otherwise specified (EDNOS). The mean age across all participants was 28.4 years and the mean BMI was 23.0.

The DTS comprises 20 questions which primarily focus on regulation of affect through the implementation of behavioral and cognitive coping strategies. It assesses tolerance for pleasant (i.e., excitement) and unpleasant (i.e., loneliness, sadness) affective states. Participants rate each item on a 5-point Likert scale ranging from 1 (“never”) to 5 (“always”), reflecting the extent to which the particular coping strategy is used in the person's everyday life. An initial exploratory factor analysis conducted by Corstorphine et al. (2007) on the mixed sample indicated that the DTS comprised three factors made up of 14 of the original 20 items. The “Avoidance of Affect” subscale describes attempts to avoid emotions (e.g., “I avoid situations that I know will make me nervous”), the “Accepting and Managing” subscale describes problem-solving to manage emotional states (e.g., “If I am feeling anxious I will do something practical to steady my nerves”, and the “Anticipate and Distract” subscale describes anticipation of distress and distraction from negative affect (e.g., “If I think that I might feel lonely, I will make sure that I am surrounded by people”). Higher scores on each subscale indicate a greater tendency to engage in that particular strategy to manage affect. The authors compared the subscale scores between the control group and the clinical group and found that patients with a diagnosed eating disorder were significantly more likely to avoid affect compared to control participants and were significantly less likely to accept and manage emotions. These findings provide initial evidence that the ability to tolerate and manage distress is diminished in patients with eating disorders, suggesting that distress tolerance is an important construct for further research. If distress tolerance is shown to be functionally related to engagement in specific eating disorder behaviors then interventions targeting distress tolerance could be adopted in treatment. Thus, it is important to establish whether the findings of Corstorphine et al. (2007) are replicable.

The present study aimed to evaluate the generalizability of the three-factor DTS model using confirmatory factor analysis with a clinical sample of patients with a DSM-IV diagnosed eating disorder. It was predicted that poor distress tolerance would be associated with elevated scores on a measure of eating disorder pathology.