Limitations
The comparability of our study population recruited from a specialized tertiary center for pediatric allergy is limited. We included only children with asthma-like symptoms and without obstructive patterns. We also excluded patients with exercise-related leading symptoms. Due to these exclusion criteria, only patients with certain conditions could be recruited onto the study. However, our findings are extracted from a real-life setting and it represents the routine diagnostic procedures. The large sample size is another strength of our study.