Development and validation of an epidermolysis bullosa family/parental burden score.

BACKGROUND The notion of the individual burden associated with a disease has been introduced to determine 'disability' in the broadest sense: psychological, social, economic and physical. Subtypes of epidermolysis bullosa (EB) are rare, life-threatening, untreatable chronic genodermatoses. OBJECTIVES To develop and validate a specific questionnaire assessing the burden on families of children with EB: Epidermolysis Bullosa Burden of Disease (EB-BoD). METHODS Items were generated by a verbatim report from parents of children with EB. Subsequently, a study was implemented for psychometric analysis. An epidermolysis bullosa burden-of-disease questionnaire was refined via item reduction according to inter-question correlations, consensus among experts and exploratory factor analysis. Internal consistency was determined by calculating Cronbach's α. Concurrent validity was determined by calculating the correlation between EB-BoD and the Short-Form 12 items (SF-12) questionnaire. RESULTS From a primary list of 30 items, EB-BoD was reduced to a 20-item questionnaire, covering four disease aspects based on the exploratory factor analysis. Construct validity was demonstrated and the EB-BoD questionnaire showed good internal consistency (Cronbach's α = 0·9). The resulting EB-BoD score was significantly correlated to the mental dimension of SF-12 (r = -0·61), but it was not correlated to it's physical dimension (r = 0·04). EB-BoD scores were significantly discriminating between EB subtypes. CONCLUSIONS The EB-BoD questionnaire appears to be a useful assessment tool regarding medical and socioeconomic issues in patients with EB and their families. EB-BoD scores correlate well with the family/parental burden experienced by the families of patients with EB.