Psychometric properties of instruments assessing exercise in patients with eating disorders: a systematic review

The Arabic Version of Compulsive Exercise Test among Saudi Population; Translation and Validation

Compulsive exercise is a condition characterized by uncontrollable exercise behaviour that may lead to severe and harmful physical and psychological consequences. Indeed, compulsive exercise is among the early symptoms of eating disorders that may affect different age groups. Globally and among Arab countries, compulsive exercise is common, while the screening methods used to assess compulsive exercise are limited. Thus, the Compulsive Exercise Test (CET) has emerged as a tool to assess cognitive, behavioural, and emotional factors related to compulsive exercise. The CET is a self-report, Likert-type scale comprising five distinct subscales. The increase in the CET scores is more likely associated with worsened pathology. Since the Arab countries lack such an assessment tool, we aimed to translate the CET into Arabic, validate the translated version, confirm the factor structures, and assess the internal consistency of the different subscales. Herein, we used the forward-backward translation method as recommended by the World Health Organization (WHO). The overall validity index of the translated version showed a score higher than 0.78, while the scale-level content validity index based on the average calculating method (S-CVI/Ave) and the agreement method (S-CVI/UA) were 0.91 and 0.58, respectively. Moreover, we recruited 399 Arabs living in Saudi to measure the internal consistency, and the value of the substantive internal consistency with Cronbach's α was 0.81. Subsequently, four of the Arabic-CET subscales had substantive internal consistency with Cronbach's α values higher than or equal to 0.70. Furthermore, the exploratory factor analysis results supported the substantial use of the five-subscale model. Taken together, our study supports using the Arabic-CET version to measure exercise compulsiveness among Arabs.

Working out measurement overlap in the assessment of maladaptive exercise

OBJECTIVE

Although exercise is generally considered healthy, many individuals engage in maladaptive exercise (e.g., compulsive in nature). Several definitions of maladaptive exercise exist, leading to multiple, varied assessment tools; assuming homogeneity across these assessments contributes to low consensus in etiological models.

METHOD

We used a Jaccard Index to quantify content overlap among 15 commonly-used self-report instruments measuring maladaptive exercise, with 31 features identified across 224 items.

RESULTS

The most common features were exercise to control weight/shape and to avoid negative affect (both included in 9/15 instruments), or compensate for calories consumed (8/15 instruments). Overlap among instruments was low (.206) and no features were common across all instruments.

CONCLUSIONS

Findings generally support theoretical models of exercise in eating pathology. However, instruments most commonly used to assess maladaptive exercise measure heterogenous content. Careful consideration should be taken when comparing findings derived from differing instruments, when synthesizing literature on maladaptive exercise, and when selecting instruments to measure specific maladaptive exercise features.

PUBLIC SIGNIFICANCE

Many, varied, tools exist for the assessment of maladaptive exercise (e.g., compulsive or compensatory) in the context of eating disorders. Assuming homogeneity across tools contributes to low consensus in the field. We used a Jaccard Index to quantify content overlap among 15 self-report instruments measuring maladaptive exercise. The most commonly used instruments measure heterogenous content. Careful consideration should be taken when synthesizing literature and selecting instruments to use in research.

Validation and measurement invariance of the Compulsive Exercise Test among Brazilian and American young adults

PURPOSE

To evaluate compulsive exercise, researchers often rely on the widely used Compulsive Exercise Test (CET). However, the measure has shown unstable factor structure in several validation studies and is not available in Portuguese for use in Brazil. We aimed to describe the translation and cultural adaptation of the CET to Brazilian Portuguese, to test several factor structures among Brazilian and US samples of men and women, to test measurement invariance across countries, and to evaluate its internal consistency. Furthermore, we sought to evaluate convergent validity, correlating the CET with a measure of eating disorder symptoms, and to compare compulsive exercise symptoms between countries.

METHODS

Four models of the latent structure of the CET were tested using confirmatory factor analyses (CFAs), three-factor structure with 15 items, three-factor structure with 18 items, four-factor structure with 21 items, and the original five-factor structure with 24 items, in a sample of 1,531 young adults (601 Brazilians and 930 Americans), aged 18-35 years.

RESULTS

A series of CFAs demonstrated that the three-factor structure with 15 items showed a better fit to the data. This model demonstrated good convergent validity and internal consistency. Results from the CET multigroup CFA showed evidence for the invariance at the configural, metric, and scalar levels across Brazilians and Americans. Furthermore, significant differences were found between Brazilians and Americans, with Brazilians demonstrating higher scores on the Avoidance and rule-driven behavior and Mood improvement subscales, whereas US participants scored higher on the Weight control exercise subscale.

CONCLUSIONS

Results support the three-factor structure with 15 items to be used as a measure of compulsive exercise among Brazilians and Americans, allowing cross-cultural comparisons between these countries.

LEVEL OF EVIDENCE

Level V, Cross-sectional, Psychometric study.

Assessment and treatment of compulsive exercise in anorexia nervosa - A combined investigation of Compulsive Exercise Activity Therapy (LEAP) and Compulsive Exercise Test subscales

INTRODUCTION

Compulsive exercise is a transdiagnostic feature of eating disorders which adversely affects aspects of recovery, such as length of hospitalisation, risk of a chronic outcome, and risk of relapse. CompuLsive Exercise Activity TheraPy (LEAP) aims to reduce compulsive exercise through a cognitive behavioural approach. This study aims to investigate the effect of LEAP on compulsive exercise behaviour using subscales of the Compulsive Exercise Test (CET), a measure of exercise in individuals with eating disorders. Predictive validity of the CET's subscales and its ability to predict eating psychopathology are investigated.

METHOD

This study used data from a randomized controlled trial of LEAP (1). Linear mixed modelling was used to investigate the effect of LEAP on compulsive exercise behaviour, and the predictive ability of CET subscales on various outcomes. The CET was compared to other exercise measures to assess its superiority in predicting eating psychopathology.

RESULTS

LEAP was superior in reducing the scores of the CET's Avoidance and Rule Driven Behaviour and Exercise Rigidity subscales. All subscales made a contribution to the respective models. The CET was superior to other measures in predicting eating pathology.

CONCLUSION

The results lend credibility to LEAP's ability to reduce core parts of compulsive exercise. The CET has been found to target important aspects of compulsive exercise behaviour, and has was superior to other exercise measures in predicting eating psychopathology.

AgRP neurons coordinate the mitigation of activity-based anorexia

Anorexia nervosa (AN) is a debilitating and deadly disease characterized by low body mass index due to diminished food intake, and oftentimes concurrent hyperactivity. A high percentage of AN behavioral and metabolic phenotypes can be replicated in rodents given access to a voluntary running wheel and subject to food restriction, termed activity-based anorexia (ABA). Despite the well-documented bodyweight loss observed in AN human patients and ABA rodents, much less is understood regarding the neurobiological underpinnings of these maladaptive behaviors. Hunger-promoting hypothalamic agouti-related peptide (AgRP) neurons have been well characterized in their ability to regulate appetite, yet much less is known regarding their activity and function in the mediation of food intake during ABA. Here, feeding microstructure analysis revealed ABA mice decreased food intake due to increased interpellet interval retrieval and diminished meal number. Longitudinal activity recordings of AgRP neurons in ABA animals exhibited a maladaptive inhibitory response to food, independent of basal activity changes. We then demonstrated that ABA development or progression can be mitigated by chemogenetic AgRP activation through the reprioritization of food intake (increased meal number) over hyperactivity, but only during periods of food availability. These results elucidate a potential neural target for the amelioration of behavioral maladaptations present in AN patients.

Compulsive exercise in eating disorders: Validation of the Italian scale and evaluation of its relationships with body image concerns and quality of life

BACKGROUND

Compulsive exercise (CE) has been proposed as one of the maladaptive elements that might concur to developing and maintaining an eating disorder (ED), even if no conclusive consensus is yet available. This study evaluates the psychometric properties of the Compulsive Exercise Test (CET), the questionnaire most frequently discussed in the literature. Our second aim is to evaluate the relationships between CE, quality of life, and different body concerns in a group of individuals.

METHODS

Two different studies are performed. In the first study, we evaluate the psychometric properties of the Italian CET with a sample of 272 individuals (157 with different diagnoses of ED). In the second study, a group of 75 ED patients is compared to 68 of their peers looking for specific differences and relationships between CE, quality of life, and body concerns.

RESULTS

The CET shows optimal psychometric proprieties, and a five-factors structure. CE is linked to more severe specific psychopathology in ED patients, including increased thoughts of restraint and concerns about weight and shape. Moreover, weight phobia and quality of life are predictors of CE in patients.

CONCLUSION

The specific role of CE is discussed according to its connections with a core psychopathological element like weight phobia. Specific profiles of CE emerged for each clinical subgroup, and they corroborate the presence of different cognitive/physical approach to exercise. The CE showed to be a dysfunctional element with a disruptive role in patients' quality of life. Future directions and possible applications of the CET are also discussed.

Development and validation of a scale for the tendency to exercise in response to mood, eating, and body image cues: the Reactive Exercise Scale (RES)

PURPOSE

Earlier work on engaging in physical exercise when experiencing negative affect demonstrated robust associations with eating disorder (ED) behaviors and attitudes; however, measurement of the behavior was primitive, relying on one yes/no question that cannot capture much variability. We report on the development of a self-report measure, the Reactive Exercise Scale (RES), that disentangles the tendency to engage in exercise in response to negative mood cues from the tendency to engage in exercise in response to eating and body image cues, which themselves may be associated with negative mood. The measure also assesses exercising in response to positive mood cues.

METHODS

Exploratory factor analysis (EFA) guided item and factor selection. Confirmatory factor analysis (CFA) in an independent sample tested a 3-factor solution-exercising in response to negative mood cues, eating and body image cues, and positive mood cues. Correlations with exercise attitudes, eating disorder and body image attitudes, mood, and personality were used to evaluate construct validity.

RESULTS

Results supported the 3-factor structure and indicated that exercising in response to negative mood cues may not uniquely relate to most aspects of ED psychopathology when accounting for eating and body image cues, which themselves are associated with negative mood.

CONCLUSION

The RES captures the tendency to exercise in response to negative mood, positive mood, and eating and body image cues. Together, these constructs allow researchers to examine the unique relations of negative mood cued exercise with ED constructs, while accounting for appearance-related motives for which exercise may also be used.

LEVEL OF EVIDENCE

Level III: evidence obtained from well-designed cohort or case-control analytic studies.

Measuring exercise in eating disorder patients: a Delphi study to aggregate clinical and research knowledge

BACKGROUND

Exercise is a prominent feature of most eating disorders, and has been shown to have a number of detrimental effects on treatment outcome. There is some disagreement in the literature regarding the construct of compulsive exercise, and assessment and treatment varies significantly. This study therefore aimed to aggregate expert clinicians' and researchers' views on how to define and measure compulsive exercise in eating disorder patients. The expert panel was also asked about questionnaire design, and possible problems when measuring compulsive exercise.

METHOD

This study used the Delphi method to establish consensus amongst an expert panel. Three successive rounds of questionnaires were distributed to the panel over a period of six months. The first round consisted of four open-ended questions regarding the definition and measurement of compulsive exercise in eating disorder patients. For Round 2, 70 statements were derived from the answers, and panelists were asked to rate each item on a Likert-based scale. An 85% consensus level was chosen. In Round 3, 44 statements were re-rated by the panel.

RESULTS

Seventeen of 24 participants completed all three rounds of the study. Consensus was achieved for 63% of the items, while 18.5% reached near consensus, and 18.5% did not reach consensus after Round 3. The panel agreed on a number of important aspects of compulsive exercise. Several suggestions regarding the format of a questionnaire assessing this behavior were also endorsed. The panel further identified common difficulties when assessing compulsive exercise in eating disorder patients, notably a lack of consensus still apparent in the literature.

CONCLUSION

The current findings constitute a further step towards a unified definition of compulsive exercise, and contribute important suggestions to the measurement of this behavior.

Management of eating disorders for people with higher weight: clinical practice guideline

INTRODUCTION

The prevalence of eating disorders is high in people with higher weight. However, despite this, eating disorders experienced by people with higher weight have been consistently under-recognised and under-treated, and there is little to guide clinicians in the management of eating disorders in this population.

AIM

The aim of this guideline is to synthesise the current best practice approaches to the management of eating disorders in people with higher weight and make evidence-based clinical practice recommendations.

METHODS

The National Eating Disorders Collaboration Steering Committee auspiced a Development Group for a Clinical Practice Guideline for the treatment of eating disorders for people with higher weight. The Development Group followed the 'Guidelines for Guidelines' process outlined by the National Health and Medical Research Council and aim to meet their Standards to be: 1. relevant and useful for decision making; 2. transparent; 3. overseen by a guideline development group; 4. identifying and managing conflicts of interest; 5. focused on health and related outcomes; 6. evidence informed; 7. making actionable recommendations; 8. up-to-date; and, 9. accessible. The development group included people with clinical and/or academic expertise and/or lived experience. The guideline has undergone extensive peer review and consultation over an 18-month period involving reviews by key stakeholders, including experts and organisations with clinical academic and/or lived experience.

RECOMMENDATIONS

Twenty-one clinical recommendations are made and graded according to the National Health and Medical Research Council evidence levels. Strong recommendations were supported for psychological treatment as a first-line treatment approach adults (with bulimia nervosa or binge-eating disorder), adolescents and children. Clinical considerations such as weight stigma, interprofessional collaborative practice and cultural considerations are also discussed.

CONCLUSIONS

This guideline will fill an important gap in the need to better understand and care for people experiencing eating disorders who also have higher weight. This guideline acknowledges deficits in knowledge and consequently the reliance on consensus and lower levels of evidence for many recommendations, and the need for research particularly evaluating weight-neutral and other more recent approaches in this field.

Behaviour, Belief and Impairment (BBI): a diagnostic procedure for eating disorders in primary care

BACKGROUND

Eating disorders are becoming increasingly prevalent, especially among adolescents. Recognition and assessment of their clinical presentation can be challenging for clinicians in primary care settings, where consultation time is short and experience with eating disorders is limited. The early detection and appropriate referral of adolescents with eating disorders are essential for timely management.

AIM

This article reviews eating disorders and the need for a simple, time-efficient assessment which could be used in primary care settings.

OUTCOME

The authors propose a unique model of assessment entitled Behaviour, Belief and Impairment or BBI, which provides a simple, time-efficient assessment that can assist in the early detection of an eating disorder. The BBI assessment model conceptualises eating disorders in three domains: the observed behaviour, the underlying belief of the patient that drives the behaviour and the subsequent physical or psychological impairment.

Psychometric properties of the Compulsive Exercise Test in a large sample of female adolescent and adult inpatients with anorexia nervosa and bulimia nervosa

OBJECTIVE

The Compulsive Exercise Test (CET) was developed to assess compulsive exercise in patients with eating disorders (EDs), but originally validated in a nonclinical sample, and psychometric properties were only investigated in small clinical samples. Therefore, the aim of this study was to examine its psychometric properties in a large clinical sample of adolescent and adult inpatients with anorexia nervosa and bulimia nervosa.

METHOD

A sample of 2,535 German female inpatients with EDs completed the CET and other instruments at admission and discharge. Factor structure (confirmatory [CFA] and exploratory factor analyses [EFA]), internal consistency and construct validity, measurement invariance across age and diagnostic groups, group comparisons of means, as well as sensitivity to change during treatment were assessed.

RESULTS

The CET showed high internal consistency, very good construct validity, and sensitivity to change. CFA indicated a better fit of four-factor and three-factor solutions compared to the original five-factor model. However, subsequent EFA identified an optimum for a five-factor model. Only three subscales were satisfactorily invariant to measurement, but not the CET total score. Only small differences in scores between patient groups were observed.

DISCUSSION

Results support internal consistency, construct validity, and sensitivity to change, whereas factor structure remains inconclusive, questioning the theoretical basis of the CET. There is limited support for using the lack of enjoyment subscale, and only moderate support for using the rigidity subscale in patients with EDs. It is recommended to further explore and/or revise the original CET, including investigation in other samples, for example, male samples.

Psychosocial etiology of maladaptive exercise and its role in eating disorders: A systematic review

OBJECTIVE

Although maladaptive exercise (ME) is widely recognized as a clinical feature in transdiagnostic eating disorders, less is known about psychosocial factors that give rise to and perpetuate this behavior. This systematic review aimed to examine the empirical status of this association.

METHOD

We reviewed 46 full text articles examining longitudinal associations between psychosocial variables and ME.

RESULTS

Eighteen studies met full inclusion criteria. Based on our qualitative synthesis, evidence suggests reasonably consistent associations between early concern with weight and shape, and negative affect on later development of ME.

DISCUSSION

Inconsistent and insufficient assessment of ME across a majority of studies underscores caution in interpretation of results, but guides important discussion for future clinical and research efforts.