Assessment of HRQoL in patients with eating disorders by the beta-binomial regression approach.
OBJECTIVE
To study the influence of clinical variables on health-related quality of life (HRQoL) among women with eating disorder (ED) using beta-binomial regression (BBR) to analyze scores on the Short-Form 36 (SF-36) as dependent variable.


METHODS
Female patients diagnosed with ED completed the SF-36 at the beginning of the study and after 2 years of treatment. Sociodemographic and clinical information was recorded. For the multivariate analysis, we used BBR models to identify factors that influence SF-36.


RESULTS
Questionnaires were completed by 193 women at baseline and 158 (82%) after 2 years of treatment. Anxiety, depression, and the severity of ED, explained scores in most domains of the SF-36 at baseline. The main predictor of HRQoL after 2 years of follow-up was the HRQoL in the same domain at baseline. However, depression, anxiety, and duration of symptoms at baseline also significantly influenced HRQoL after 2 years of treatment in some domains. Higher levels of anxiety or depression, longer duration of symptoms, and poorer SF-36 scores at baseline were associated with worse HRQoL after 2 years of treatment and follow-up.


CONCLUSIONS
BBR models provide understandable results for clinicians and can be used in multivariate models with HRQoL dependent variables.
Arostegui
Inmaculada
I
Departamento de Matemática Aplicada y Estadística e Investigación Operativa, Universidad del País Vasco, Leioa, Bizkaia, Spain. inmaculada.arostegui@ehu.es
Padierna
Angel
A
Quintana
Jose M
JM
D001007:Anxiety / Q000523:psychology; D016009:Chi-Square Distribution; D003863:Depression / Q000523:psychology; D001068:Feeding and Eating Disorders / Q000523:psychology*; D005260:Female; D006304:Health Status; D006801:Humans; D016017:Odds Ratio; D011446:Prospective Studies; D011788:Quality of Life / Q000523:psychology*; D012044:Regression Analysis; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires