Beyond the 5th percentile: rethinking diagnostic thresholds in pulmonary function testing

<title>Extract</title> This manuscript has recently been accepted for publication in the <italic>European Respiratory Journal</italic>. It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the <italic>ERJ</italic> online. Please open or download the PDF to view this article. Statistical thresholds such as the LLN define rarity, not disease. Evidence shows that clinically meaningful lung disease often emerges above the 5th percentile, suggesting the need to align diagnostic thresholds with risk rather than distribution.