OBJECTIVES: To develop a questionnaire assessing the impact on parents of an infant's hospitalization for bronchiolitis. Bronchiolitis is a viral respiratory infection of the bronchioles most commonly caused by the respiratory syncytial virus. It usually affects infants of less than 2 years, particularly following premature delivery, bronchopulmonary dysplasia or congenital heart disease. Although generic questionnaires about the impact of a child's disease on family are available, no specific questionnaire linked to bronchiolitis hospitalization exists. METHODS: A multidisciplinary scientific committee was set up and included in the whole process of questionnaire development. A literature review, 3 clinician interviews and 18 exploratory interviews with parents of children hospitalized for bronchiolitis were conducted in parallel. The concepts identified were organised into a model. Items were generated for each concept using parents' words. The Impact of Bronchiolitis Hospitalization Questionnaire (IBHQ©) was developed in French to be completed by the parent who was the most often present at the hospital, within the seven days after bronchiolitis hospitalization, and again three months after hospitalization. The IBHQ© was tested for relevance and comprehension with nine new parents, and revised accordingly. RESULTS: Items generated for each concept identified were organised into eight sections: parents' emotional impact, infant's reactions, parents' physical impact, impact on daily organization, siblings' reactions, parents' behaviour with infant and siblings, impact on couple, and financial consequences. Except a few items that were modified or deleted following parents' suggestions, most of the items were well understood, and considered relevant and adequate by parents during comprehension tests. The revised IBHQ© contains 65 items. CONCLUSIONS: The IBHQ© is a unique and promising tool that provides a comprehensive evaluation of the impact of a child's bronchiolitis hospitalization on parents. An observational study is currently under way to validate psychometric properties and scoring of the questionnaire.