Table 2

Infant details at time of lung function test

Infants with CF (n=71)Healthy controls (n=54)Δ (95% CI) CF – controlsp Value
Age at test*, weeks11.4 (2.3)12.2 (2.0)–0.82 (–1.59 to –0.06)0.043
Weight, kg5.32 (0.84)6.05 (0.78)–0.73 (–1.02 to –0.45)<0.001
Weight, z-score –0.75 (1.08)0.06 (1.93)–0.81 (–1.17 to –0.45)<0.001
Length, cm59.2 (2.7)61.6 (2.3)–2.4 (–3.3 to –1.7)<0.001
Length, z-score –0.14 (1.04)0.72 (0.86)–0.86 (–1.19 to –0.52)<0.001
Body mass index15.1 (1.6)15.9 (1.4)–0.8 (–1.3 to –0.3)0.005
Body mass index, z-score –0.94 (1.08)–0.47 (0.98)–0.47 (–0.84 to –0.10)0.013
Change in weight z-score (3 month – birth)–0.42 (1.06)0.05 (1.00)–0.46 (–0.83 to –0.10)0.014
  • Unless stated otherwise, data presented as mean (SD).

  • * Postnatal age at test corrected for gestational age.

  • Calculated using UK WHO algorithms.25

  • CF, cystic fibrosis; Δ, mean difference between groups.