Eating disorders have a profound and highly specific impact on psychosocial functioning. The aim of this research was to develop a measure of such secondary impairment. A 16-item, self-report instrument was developed, the Clinical Impairment Assessment (CIA), which was designed to measure such impairment overall and in three specific domains (personal, cognitive, social). The psychometric properties of the instrument were evaluated using data collected in the context of a transdiagnostic treatment trial. The findings consistently supported the utility of the instrument with the CIA being shown to have high levels of internal consistency, construct and discriminant validity, test–retest reliability, and sensitivity to change. The CIA should be of value to clinicians when assessing patients with eating disorders and their response to treatment. It should also help inform epidemiological research.
The assessment of psychopathology requires not only an evaluation of the nature and severity of particular features, but also an assessment of the impact of these features on the person's psychosocial and physical functioning. This is important for at least two reasons: first, it is often impairment that leads people to seek help and a goal of treatment should therefore be to reduce it; and second, the presence of clinically significant impairment is required to make a diagnosis of a mental disorder (American Psychiatric Association, 1994). Despite this, measures of psychopathology have tended to focus on the psychopathology itself and not the impairment that it causes. Recently this tendency has been countered to an extent with the increasing use of measures of “health-related quality of life” to supplement the assessment of symptoms. Although valuable, these generic measures, developed originally to assess the impact of physical illnesses on everyday functioning (Ware et al., 1996, Ware et al., 1993 and WHOQOL Group, 1998), may miss important sources of impairment that are peculiar to psychopathology and to the characteristics of particular psychiatric disorders.
Eating disorders are a case in point for they have profound and specific effects on psychosocial functioning. For example, these patients' over-evaluation of shape and weight and its expressions, the so-called “core psychopathology” (Fairburn, 2008), has a marked effect on their ability to be with others and to form intimate personal relationships. Similarly, their concerns about eating, and its expressions, prevent them from eating healthily, affecting their mood, cognitive function and family relationships. Secondary effects of this type can be extremely disabling yet are likely to be missed by generic measures of health-related quality of life (Doll, Petersen, & Stewart-Brown, 2005). For this reason disorder-specific measures are required.
Four eating disorder-specific measures of health-related quality of life have recently been developed (Abraham et al., 2006, Adair et al., 2007, Engel et al., 2006 and Las Hayas et al., 2006). However, none of the four measures is entirely satisfactory as a measure of impairment secondary to the whole range of eating disorder psychopathology. The main problems are as follows. First, three of the instruments confound the measurement of eating disorder psychopathology with the assessment of impairment and fail to ensure that the impairment assessed is secondary to eating disorder psychopathology (Abraham et al., 2006, Adair et al., 2007 and Las Hayas et al., 2006). Second, three instruments omit to assess the impact of the patients' extreme concerns about their shape (Abraham et al., 2006, Engel et al., 2006 and Las Hayas et al., 2006) and as a result are likely to underestimate the extent of the secondary impairment. Third, sensitivity to change was only examined in one of the four studies (Abraham et al., 2006). Fourth, none of the instruments have been validated against independent assessments of the extent of secondary impairment and none has been evaluated in terms of its ability to predict case status.
The aim of the present study was to develop a clinically useful measure of the psychosocial impairment that results from eating disorder features and to test its reliability, validity, sensitivity to change and ability to predict case status.
