Diagnosing asthma in children: what is the role for methacholine bronchoprovocation testing?

Objective: To determine whether measurement of airways responsiveness to methacholine can help physicians diagnose asthma in children.

Methods: Children from the 1995 Manitoba birth cohort were assessed by asthma specialists, had skin testing and measurement of airways responsiveness to methacholine (PC20). We selected children with doctor-diagnosed asthma and healthy children as controls (no asthma, no allergic rhinitis, negative skin tests).