Table 3

Univariate negative binomial regression models for pulmonary exacerbations in the year following the baseline measurement

Predictor  βSE (β)Wald χ2p ValueRate ratio95% CI of rate ratio
LCI z-score0.110.0311.90.0011.121.051.19
FEV1 z-score−0.540.1710.30.0010.580.420.81
CFCS0.150.058.30.0041.161.051.29
FEF25–75 z-score−0.380.138.30.0040.690.530.89
Ps.a positive*0.900.405.50.0232.461.135.36
CFQ-Rresp−0.030.015.30.0210.970.940.99
Age in years0.100.053.90.0491.101.001.22
Female gender0.500.391.60.1991.650.773.53
  • *≥1 positive culture for Pseudomonas aeruginosa in the 12 months preceding the baseline measurement.

  • CFCS, Cystic Fibrosis Clinical Score; CFQ-Rresp, respiratory domain of the Cystic Fibrosis Questionnaire-Revised; FEF25–75, forced expiratory flow between 25% and 75% of forced vital capacity; FEV1, forced expiratory volume in 1 s; LCI, lung clearance index; Ps.a, Pseudomonas aeruginosa.