Burden of adult neurofibromatosis 1: development and validation of a burden assessment tool

BACKGROUND: Neurofibromatosis Type 1 (NF1) is a common genetic neurocutaneous disease, with an autosomal dominant inheritance mode. Quality of life has been shown impaired in NF1, due to severe complications, cosmetic features, and uncertainty about the disorder. METHODS: This study sought to develop a self-administered questionnaire in French to assess the burden of NF1 (BoN), then translate and linguistically and cross-culturally validate it into American English, standardized methodology applied, as outlined in the report. RESULTS: Based on several discussions with NF1 patients, a 17-item conceptual questionnaire was first produced. Of the 91 NF1 adult patients who responded to the conceptual questionnaire, 65 (64.6% females) were accessible. Subsequent confirmatory analyses generated a 15-item questionnaire grouped into four domains, demonstrating internal consistency (Cronbach’s alpha: 091), discriminant validity, and high reliability. The BoN was likewise shown to significantly correlate with other validated questionnaires, such as Dermatology Life Quality Index, Perceived Stress Scale, and SF12 mental score, indicating good external validity. CONCLUSIONS: BoN is a specific tool for assessing the burden that NF1 generates on many practical aspects of the patient daily activities, beyond the notion of quality of life”. Given the increasing relevance that regulatory authorities attribute to patient-reported outcomes, the BoN questionnaire provides such supplementary information while accounting for the burden of NF1 patients in the broadest sense. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s13023-019-1067-8) contains supplementary material, which is available to authorized users.