Population characteristics during the baseline period
During the study period, clinical data from 712 patients with CF were available in the clinical database and EMR, of whom 294 met inclusion criteria (Figure S1). At baseline, 113 patients (38%) were categorized as having frequent fungi and 181 patients had rare fungus (62%). Patient characteristics during the two-year baseline period are shown in Table 1. Aspergillus sp . was the most common fungus isolated in the baseline period for both the frequent and rare groups, with Aspergillus fumigatus being the most common. Individuals categorized as frequent fungi were older (median 13.7 versus 11.7 years, p = 0.02) and were more frequently co-infected with S. maltophilia (35% versus 17%, p < 0.001) compared to those with rare fungus. We did not detect differences in baseline ppFEV1, BMI percentile or rates of ABPA between groups. Fewer individuals with frequent fungi were diagnosed with asthma compared to the rare fungus group (14.9% versus 25.6%, p = 0.04).