Table 3—

Pearson's correlation coefficients between efficacy endpoints

Efficacy endpointsMeanMedian (range)
FEV1 and measured-at-clinic PEF0.850.86 (0.75–0.88)
FEV1 and patient-reported PEF0.740.75 (0.70–0.76)
FEV1 and daytime symptom−0.13−0.13 (−0.17–−0.08)
FEV1 and β-agonist use−0.22−0.22 (−0.26–−0.18)
Measured-at-clinic and patient-reported PEF0.770.78 (0.69–0.80)
Daytime symptom and measured-at-clinic PEF−0.15−0.16 (−0.19–−0.09)
Daytime symptom and patient-reported PEF−0.19−0.19 (−0.22–−0.15)
Daytime symptom and β-agonist use0.550.58 (0.42–0.62)
β-agonist use and measured-at-clinic PEF−0.20−0.21 (−0.30–−0.09)
β-agonist use and patient-reported PEF−0.23−0.22 (−0.27–−0.17)
  • Across visit-specific correlations over time

  • FEV1: forced expired volume in one second

  • PEF: peak expired flow

  • All correlations were significantly different from zero (p<0.005)