5. Strengths and limitations
The French CobraPed cohort has enrolled a subsequent and well-characterized population. In particular, preschoolers represent a significant number, of whom 61 could be included in the cluster analysis on the basis of positivity to at least one c-sIgE, providing more information than previously (10). However, this study had several limitations. We excluded patients receiving the anti-IgE omalizumab. Although the biological rationale behind this choice is clear, we excluded severe asthmatic patients, often highly atopic with multiple sensitizations (30,31). However, because omalizumab was mostly offered to school-age children, per guidelines, the results for the preschoolers was not influenced by this bias. In addition, we applied a strict definition for SRW and SA based on the current guidelines at the time of enrollment (12). Consequently, the patients with SRW/SA had a high burden, with frequent symptoms, exacerbations, and alteration of lung function and were representative of these children.