Validation of the Spanish version of the eating disorders quality of life instrument (EDQOL)

J Eat Disord. 2023 Jun 28;11(1):103. doi: 10.1186/s40337-023-00832-w.

Abstract

Background: The Eating Disorders Quality of Life instrument (EDQOL) is a disease-specific health related quality of life self-report questionnaire designed for disordered eating patients. Although the EDQOL is one of the most suitable and widely used questionnaires in many countries, no prior research has addressed the psychometric properties of the Spanish adaptation of the EDQOL. Therefore, the aim of this study is to examine the psychometric properties of the Spanish version of the EDQOL among ED patients.

Methods: 141 female eating disorder patients, with a mean age of 18.06 years (SD = 6.31), completed the EDQL in addition to the Eating Disorder Examination Questionnaire (EDEQ), the Depression, Anxiety and Stress Scales (DASS-21), the Clinical Impairment Assessment (CIA 3.0) and the Health Survey (SF-12). We calculated item/scale characteristics, internal consistencies and bivariate correlations with other measures of quality of life and adjustments. We assessed the goodness-of-fit of the 4-factor model using confirmatory factors analysis and explored the sensitivity of change following skill-based interventions.

Results: The fit of the 4-factor model was acceptable (Root Mean Square Error of Approximation: 0.07, Standard Root Mean Square Residual: 0.07). Cronbach's alpha was excellent for the total (.91) and acceptable for all subscales (0.78-0.91). The construct validity was found with measures of psychological distress, depression, anxiety, quality of life and clinical impairment. The psychological and physical/cognitive scales and the EDQOL global scale were responsive to change.

Conclusion: The Spanish EDQOL version is a useful instrument to assess quality of life in eating disorder patients and to evaluate outcomes of skills-based interventions.

Keywords: EDQOL; Eating disorders; Psychometrics; Quality of life; Validation.

Plain language summary

Eating Disorders (EDs) have a severe impact on many domains of quality of life (QOL). Therefore QOL needs to be addressed in effectiveness research and clinical practice. Furthermore, QOL is a very relevant concept in the treatment of chronic diseases and its evaluation requires specific health-related questionnaires. One widely used self-report measure to assess the quality of life in eating disorders is the Eating Disorder Quality of Life (EDQOL). Despite its high clinical relevance, EDQOL has not been previously investigated in the Spanish context. To overcome this gap, the present study aimed to validate the Spanish version of the EDQOL in a sample of Spanish eating disorder patients. The findings showed that the Spanish version of the EDQOL is robust in terms of reliability, factor structure and construct validity. This questionnaire may be preferred by clinicians and researchers interested in ED-specific health related quality of life impairment and as an additional indicator of ED severity.