To track or not to track: wheeze phenotypes in preschool children

Extract

We applaud the robust statistical approach used by Spycher et al. [1] to assess the temporal stability of episodic viral wheeze (EVW) and multitrigger wheeze (MTW) phenotypes in young children. They reported that in two large population-based cohort studies, children who continued to wheeze at 4 and 6 years of age showed a tendency to maintain the same phenotype from the age of 2 years. The authors' conclusion, and that of the accompanying editorial, is that the EVW and MTW phenotypes in young children are stable and track over time [2], and that these phenotypes may represent different disease entities [1, 2]. We would like to call for caution in interpreting these results because they are based on statistical probability, not on clinical differential diagnosis.