Table 3

Parent–child concordance

Parent–childMother–childFather–child
Pearson’s correlationNCC95% CINCC95% CINCC95% CI
 Raw
   FEV1 16680.190.15 to 0.2414540.200.15 to 0.252140.210.07 to 0.33
   FVC16680.210.17 to 0.2614540.240.19 to 0.292140.200.07 to 0.33
   FEV1/FVC ratio16680.230.18 to 0.2714540.240.19 to 0.292140.170.04 to 0.30
   MEF (FEF25%–75%)16680.200.15 to 0.2414540.210.16 to 0.262140.150.02 to 0.28
 z-Score
   FEV1 16530.220.17 to 0.2614390.220.17 to 0.272140.250.12 to 0.38
   FVC16530.240.20 to 0.2914390.250.20 to 0.292140.220.09 to 0.35
   FEV1/FVC ratio16530.250.20 to 0.2914390.260.21 to 0.302140.210.08 to 0.34
   MEF16530.240.20 to 0.2914390.240.19 to 0.292140.260.13 to 0.38
Adjusted linear regressionNRCP valueNRCP valueNRCP value
 Raw
   FEV1 16100.16<0.00114350.16<0.0011750.19<0.001
   FVC16100.17<0.00114350.17<0.0011750.150.001
   FEV1/FVC ratio16100.26<0.00114350.26<0.0011750.210.004
   MEF (FEF25%–75%)16100.19<0.00114350.20<0.0011750.17<0.001
 z-Score
   FEV1 15980.21<0.00114230.21<0.0011750.29<0.001
   FVC15980.24<0.00114230.25<0.0011750.300.001
   FEV1/FVC ratio15980.28<0.00114230.29<0.0011750.240.002
   MEF15980.25<0.00114230.25<0.0011750.30<0.001
  • Covariates models include child and parental age, sex BMI and current parental smoking.

  • N, number of biological child–parent pairs with this measure.

  • CC, Pearson’s correlation coefficients; FEF, forced expiratory flow; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; MEF, mid expiratory flow; RC, estimated regression coefficient.