Bulimic Behaviour Observation Questionnaire (COBU): Developing an instrument for caregivers of patients with bulimia nervosa

Abstract

The aim was to develop and evaluate the psychometric properties of the Bulimic Behaviour Observation Questionnaire (COBU), related to the symptoms observed in bulimia nervosa (BN) by caregivers. The sample consisted of 162 caregivers of patients with BN (n=126), anorexia nervosa (AN) (n = 26) and binge eating disorder (n =10). Exploratory analysis of the COBU revealed three factors: Overeating observation (α = 0.77), Restriction Interval Observation (α = 0.76) and Impulsivity Observation (α = 0.62). The questionnaire showed good convergent validity with the ABOS scale for carers (rho = 0.58), p < .01) and the BITE scale for patients (rho = 0.40, p < 0.01). The questionnaire discriminates between clinical diagnoses, except for the Impulsivity Observation subscale. It is recommended for use in the assessment by the family and to assist in recognizing and assessing changes in the symptoms.