Data is presented as n or mean (95% CI) unless otherwise stated. Mean z-scores and 95% CI for each group were derived after adjusting for the remaining characteristics. ^#: total number of subjects (N) was 1601. ^¶: likelihood ratio test p-value indicating whether the characteristic explains differences in height within the study population. ⁺: age at measurement (numbers represent the unique number of patients in each group, however, patients can be included in more than one group). ^§: patients from Serbia were excluded from this analysis because no national references were available. ^ƒ: defined as hallmark PCD electron microscopy findings and/or biallelic gene mutation, identified based on the ERS PCD Diagnostics Task Force guidelines. ^##: abnormal light or high frequency video microscopy finding and/or low nasal NO value.