Limitations and strengths
One limitation of this cross-sectional study is the absence of longitudinal evaluation that would allow phenotype-specific trends in disease progression and pulmonary functions to be monitored over time. We also acknowledge that definitions of symptoms, medication use and environmental exposures used in our models are based on parental reporting using interviewer-administered questionnaires, and that this may reduce the accuracy of the results by introducing bias in the responses of the study parents (e.g. inaccurate recall, misreported information and/or interaction between respondent and interviewer).
The key advantage of our study is the availability of data from a large study population with similar characteristics, a well-defined clinical diagnosis and objective measures such as SPT. LCA enabled us to identify novel clinical clusters in children with AR.