McNally P, et al. - Bronchoalveolar lavage (BAL) is a potentially useful outcome measure for clinical trials in children with CF but its use is limited by variations in approach internationally. This study was implemented to determine whether pooling adversely influenced the diagnostic properties of BAL. Findings demonstrated no adverse effect of pooling of BAL in children on either the detection of pulmonary infection or inflammation or the observed link between infection and inflammation. Furthermore, regional differences in inflammation were suggested by the observed intra-patient variability in BAL interleukin-8 levels.