Assessment of quality of life in people with severe and enduring anorexia nervosa: a comparison of generic and specific instruments
Background: Criticisms that generic measures of health-related quality of life (HRQoL) are not sensitive to impairment in anorexia nervosa (AN) has spurred the development of disease-specific measures. This study aimed to compare the psychometric properties of a generic to a disease-specific measure of HRQoL.
Methods: 63 participants with AN completed measures of a generic HRQoL (SF-12), disease-specific HRQoL (Eating Disorders Quality of Life Questionnaire; EDQOL), functional impairment (days out of role; DOR; Work and Social Adjustment Scale; WSAS), and eating disorder severity (Eating Disorder Examination; EDE) at baseline, post-treatment, and 6- and 12-months follow-up. Cronbach’s α was computed for the SF-12 and EDQOL (internal consistency). Correlations were assessed between SF-12/EDQOL scores and DOR, WSAS, and EDE scores (convergence validity). Three sets of three multiple linear regressions were performed using SF-12 and EDQOL scores as predictors and change in DOR, WSAS, and EDE global scores from baseline to (i) post-treatment, (ii) 6-month follow-up, (iii) and 12-month follow-up as dependent variables (predictive validity and sensitivity).
Results: The EDQOL displayed stronger internal consistency (α = 0.92) than the SF-12 (α = 0.80). The SF-12 converged more strongly with DOR and the WSAS (rp = −0.31 to −0.63 vs. 0.06 to 0.70), while the EDQOL converged more strongly with the EDE (rp = −0.01 to 0.48 vs. -0.01 to −0.37). The SF-12 demonstrated stronger predictive validity (β = −0.55 to 0.29) and sensitivity to changes in ED severity (β = −0.47 to 0.32).
Conclusions: The SF-12 is a valid and sensitive measure of HRQoL impairment in patients with AN. While the SF-12 may be preferred in research comparing EDs to other populations, and in research and practice as an indicator of functional impairment; the EDQOL may be preferred by clinicians and researchers interested in HRQoL impairment specifically associated with an ED and as an additional indicator of ED severity.
History
Publication title
BMC psychiatryVolume
13Article number
284Number
284Pagination
1-9ISSN
1471-244XDepartment/School
School of Health SciencesPublisher
BioMed CentralPlace of publication
United KingdomRights statement
Copyright 2013 Mitchison et al.; licensee BioMed Central Ltd. Licensed under Creative Commons Attribution 2.0 Generic (CC BY 2.0) https://creativecommons.org/licenses/by/2.0/Repository Status
- Open